[{"data":1,"prerenderedAt":265},["ShallowReactive",2],{"tag-labels":3,"site-header":4,"article-python-class-object-en":72},{},{"featuredPost":5,"navigations":29},{"id":6,"title":7,"title_id":8,"slug":9,"excerpt":10,"excerpt_id":11,"has_translation":12,"published_at":13,"reading_time":14,"hidden_from_listing":15,"tags":16,"thumbnail_image":21,"og_image":22,"series":23,"authors":28},110,"When You Pick a Framework Just to Look Different","Ketika Pilih Framework Cuma Biar Kelihatan Beda","ketika-pilih-framework-cuma-biar-kelihatan-beda","The last time you chose a new framework or library, was it because your problem needed that tool, or because it sounded cool and few people around you were using it? That question is uncomfortable. Technology decisions are often made for reasons that never appear in any technical document.","Terakhir kali kamu milih framework atau library baru, itu karena masalahmu butuh alat itu, atau karena alatnya kedengaran keren dan belum banyak yang pakai? Pertanyaan ini nggak enak dijawab. Soalnya keputusan teknologi sering diambil dengan alasan yang nggak pernah ditulis di dokumen teknis mana pun.",true,"2026-10-06T15:25:21.000Z",5,false,[17,18,19,20],"karier","framework","opini","pengalaman",null,"\u002Fog\u002Fketika-pilih-framework-cuma-biar-kelihatan-beda.png",{"id":24,"title":25,"title_id":26,"slug":27},9,"Articles","Artikel","all",[],[30,46,67],{"collection":31,"item":32},"series",{"__typename":31,"title":25,"title_id":26,"slug":27,"children_series":33},[34,38,42],{"title":35,"title_id":36,"slug":37},"Artificial Intelligence","Kecerdasan Artifisial","kecerdasan-artifisial",{"title":39,"title_id":40,"slug":41},"Programming Fundamentals","Konsep Dasar Pemrograman","konsep-dasar-pemrograman",{"title":43,"title_id":44,"slug":45},"Algorithms and Data Structures","Algoritma dan Struktur Data","algoritma-struktur-data",{"collection":31,"item":47},{"__typename":31,"title":48,"title_id":48,"slug":49,"children_series":50},"Tutorial","tutorial",[51,55,59,63],{"title":52,"title_id":53,"slug":54},"Learning Python","Belajar Python","belajar-python",{"title":56,"title_id":57,"slug":58},"Learning Go","Belajar Golang","belajar-golang",{"title":60,"title_id":61,"slug":62},"Learning Java","Belajar Java","belajar-java",{"title":64,"title_id":65,"slug":66},"Learning Pascal","Belajar Pascal","belajar-pascal",{"collection":31,"item":68},{"__typename":31,"title":69,"title_id":69,"slug":70,"children_series":71},"Lab","lab",[],{"article":73,"renderedBody":152,"renderedTakeaway":153,"latestArticles":154,"toc":254},{"id":74,"title":75,"title_id":76,"slug":77,"excerpt":78,"excerpt_id":79,"has_translation":12,"published_at":80,"reading_time":14,"hidden_from_listing":15,"tags":81,"thumbnail_image":21,"og_image":84,"series":85,"authors":144,"seoTitle":21,"seoDescription":21,"body_locale":147,"available_locales":148,"body":150,"takeway":151,"prerequisite":21},139,"Python Classes: the History Every Account Shared","Python Class: Riwayat yang Dipakai Bersama Semua Akun","python-class-object","Two accounts, and each history lists the other account's deposits. The list sat in the class body, `append` never writes to the object, so both accounts appended into the same one.","Dua akun, dan riwayat masing-masing memuat setoran akun lain. List-nya duduk di body class, `append` tidak pernah menulis ke objek, jadi kedua akun menambah ke list yang sama.","2026-11-07T01:00:00.000Z",[82,83],"python","oop","\u002Fog\u002Fpython-class-object.png",{"id":86,"title":52,"title_id":53,"slug":54,"description":87,"description_id":21,"articles":88,"children_series":98,"parent_series":135},10,"Python from zero: the shape of the language, why it reads the way it does, and where it's the right tool.",[89],{"id":74,"title":75,"title_id":76,"slug":77,"excerpt":78,"excerpt_id":79,"has_translation":12,"published_at":80,"reading_time":14,"hidden_from_listing":15,"tags":81,"thumbnail_image":21,"og_image":84,"series":90,"authors":91},{"id":86,"title":52,"title_id":53,"slug":54},[92],{"authors_id":93},{"id":94,"name":95,"slug":96,"role":97,"profile_picture":21},1,"Daffa Izzuddin","izzudd","Writer",[99,105,111,117,123,129],{"id":100,"title":101,"title_id":102,"slug":103,"description":104,"cover_image":21},16,"Getting Started with Python","Berkenalan dengan Bahasa Python","python-intro","Your first step with Python: meet the language, install Python 3, poke around the interpreter, and get the syntax.",{"id":106,"title":107,"title_id":108,"slug":109,"description":110,"cover_image":21},17,"Variables, Types, and Operations","Variabel, Tipe Data, dan Operasi","python-variabel-tipe-data","Create variables, then meet the types one by one, from numbers and strings to booleans and the list that keeps tripping up beginners.",{"id":112,"title":113,"title_id":114,"slug":115,"description":116,"cover_image":21},18,"Working with Python Scripts","Menggunakan Script Python","python-pemrograman-dengan-script","Leave the interpreter and start writing real .py files, including how to take input and print output.",{"id":118,"title":119,"title_id":120,"slug":121,"description":122,"cover_image":21},19,"Control Structures","Struktur Kontrol","python-struktur-kontrol","Make a program decide things and repeat work: branching, loops, and list comprehension.",{"id":124,"title":125,"title_id":126,"slug":127,"description":128,"cover_image":21},20,"Functional Programming with Python","Pemrograman Fungsional dengan Python","python-pemrograman-fungsional","Wrap your code in functions so you stop writing the same thing twice. Parameters, return values, and default arguments.",{"id":130,"title":131,"title_id":132,"slug":133,"description":134,"cover_image":21},30,"Collections and Strings","Koleksi dan String","python-collections","Dictionaries, sets, tuples, and the string methods that do the boring parts. The types you need once a program stops holding a single value.",{"id":94,"title":48,"title_id":48,"slug":49,"parent_series":21,"children_series":136},[137,138,140,142],{"id":86,"title":52,"title_id":53,"slug":54,"cover_image":21},{"id":139,"title":56,"title_id":57,"slug":58,"cover_image":21},11,{"id":141,"title":60,"title_id":61,"slug":62,"cover_image":21},13,{"id":143,"title":64,"title_id":65,"slug":66,"cover_image":21},14,[145],{"authors_id":146},{"id":94,"name":95,"slug":96,"role":97,"profile_picture":21},"en",[147,149],"id","Your bank-account report prints Ani's deposit inside Budi's history. The balances are right and nothing raised an error, so nothing pointed at the class body. That is where the bug lives: a mutable *class attribute* that every account shares.\n\nHere is the output from a script that builds `Account(\"Ani\", 100)` and `Account(\"Budi\", 0)`, then calls `ani.deposit(50)` and `budi.deposit(20)`:\n\n```text\nani.balance 150\nbudi.balance 20\nani.history ['Ani deposit 50', 'Budi deposit 20']\nbudi.history ['Ani deposit 50', 'Budi deposit 20']\nsame list: True\nAccount.history ['Ani deposit 50', 'Budi deposit 20']\nani.__dict__ {'owner': 'Ani', 'balance': 150}\n```\n\nRead the last line. Ani's `__dict__` holds `owner` and `balance`, and no `history`. The attribute was never set on the object, so the lookup found the class's list.\n\nReading `self.history` looks on the object first, then on the class. `self.history.append(x)` is a method call on whatever list that lookup returned. It is not an assignment, so nothing gets written to the object. The [Python tutorial on classes](https:\u002F\u002Fdocs.python.org\u002F3\u002Ftutorial\u002Fclasses.html) covers this lookup order.\n\n## Two files, one command\n\nStart with the broken version. The list sits in the class body, above `__init__`:\n\n```python\n# account.py\nclass Account:\n    history = []\n\n    def __init__(self, owner, balance=0):\n        self.owner = owner\n        self.balance = balance\n\n    def deposit(self, amount):\n        self.balance = self.balance + amount\n        self.history.append(f\"{self.owner} deposit {amount}\")\n```\n\nNext, a checker. It builds two accounts, makes one deposit in each, and asks four questions:\n\n```python\n# check_account.py\nimport account\n\npassed = 0\ntotal = 0\n\n\ndef check(name, ok, detail=\"\"):\n    global passed, total\n    total += 1\n    if ok:\n        passed += 1\n        print(f\"PASS  {name}\")\n    else:\n        print(f\"FAIL  {name}  \u003C- {detail}\")\n\n\nani = account.Account(\"Ani\", 100)\nbudi = account.Account(\"Budi\", 0)\n\nani.deposit(50)\nbudi.deposit(20)\n\ncheck(\"a deposit lands in the account that made it\", ani.balance == 150, f\"balance is {ani.balance}\")\ncheck(\"the other account's balance does not move\", budi.balance == 20, f\"balance is {budi.balance}\")\ncheck(\n    \"each account has one line of history\",\n    len(ani.history) == 1 and len(budi.history) == 1,\n    f\"ani has {len(ani.history)}, budi has {len(budi.history)}\",\n)\ncheck(\n    \"the two history lists are different lists\",\n    ani.history is not budi.history,\n    \"both accounts point at the same list\",\n)\n\nprint()\nprint(f\"{passed} of {total} checks passed\")\nraise SystemExit(0 if passed == total else 1)\n```\n\nRun `python3 check_account.py` with the starter in place. It exits with code 1:\n\n```text\nPASS  a deposit lands in the account that made it\nPASS  the other account's balance does not move\nFAIL  each account has one line of history  \u003C- ani has 2, budi has 2\nFAIL  the two history lists are different lists  \u003C- both accounts point at the same list\n\n2 of 4 checks passed\n```\n\nTwo checks already pass, and that is the trap. `self.balance = ...` is an assignment, and assignment always writes on the object, so each account gets its own `balance`. `self.history.append(...)` never assigns anything. Balances are the first thing you would test, and they look fine.\n\nNow move the list into `__init__`, so each object creates its own:\n\n```python\n# account.py\nclass Account:\n    def __init__(self, owner, balance=0):\n        self.owner = owner\n        self.balance = balance\n        self.history = []\n\n    def deposit(self, amount):\n        self.balance = self.balance + amount\n        self.history.append(f\"{self.owner} deposit {amount}\")\n```\n\nRun the same command again. This time it exits with code 0:\n\n```text\nPASS  a deposit lands in the account that made it\nPASS  the other account's balance does not move\nPASS  each account has one line of history\nPASS  the two history lists are different lists\n\n4 of 4 checks passed\n```\n\nI ran all of this on Python 3.14.9 on Linux. I did not try other Python versions, so this is the evidence from one machine.\n\n## What this does not do\n\nA class attribute is still the right home for a value nobody mutates. The checker cannot tell a shared constant from a shared list, and it should not. Sharing was never the problem. Mutating something shared was.\n\nAn empty `history` is also not proof that you fixed it. Every account starts with an empty list in both versions. The bug only shows once a second object exists, which is exactly what the checker builds.\n\n## Break it on purpose\n\nPut `history = []` back in the class body. Then add one line to `__init__`:\n\n```python\nself.history = Account.history\n```\n\nIt looks like each account now gets its own list. Run the checker and two checks fail again:\n\n```text\nPASS  a deposit lands in the account that made it\nPASS  the other account's balance does not move\nFAIL  each account has one line of history  \u003C- ani has 2, budi has 2\nFAIL  the two history lists are different lists  \u003C- both accounts point at the same list\n\n2 of 4 checks passed\n```\n\nThe new line copies the same list object into both objects, so the objects still share it.\n\nBefore you put a list, dict, or set in a class body, ask one question: should a second object see this change? If yes, share it on purpose. If no, build it in `__init__`.\n\n","- A list assigned in the class body belongs to the class, so every object reads that same list until the object gets one of its own.\n- `self.history.append(x)` reads the class attribute and mutates it; it never writes an attribute on the object, which is why `history` is absent from `ani.__dict__`.\n- `self.balance = ...` looked correct because assignment always writes on the object that holds the name.\n- Build mutable state in `__init__`, and leave a class attribute for values no object should be able to change.","\u003Cp>Your bank-account report prints Ani's deposit inside Budi's history. The balances are right and nothing raised an error, so nothing pointed at the class body. That is where the bug lives: a mutable \u003Cem>class attribute\u003C\u002Fem> that every account shares.\u003C\u002Fp>\n\u003Cp>Here is the output from a script that builds \u003Ccode>Account("Ani", 100)\u003C\u002Fcode> and \u003Ccode>Account("Budi", 0)\u003C\u002Fcode>, then calls \u003Ccode>ani.deposit(50)\u003C\u002Fcode> and \u003Ccode>budi.deposit(20)\u003C\u002Fcode>:\u003C\u002Fp>\n\n\u003Cdiv class=\"code-block-wrapper my-6 not-prose rounded-xl border-2 border-black dark:border-gray-600 shadow-neo overflow-hidden bg-[#24292e] text-[#e1e4e8] transition-all\">\n  \u003Cdiv class=\"code-block-header flex items-center justify-between px-4 py-2.5 bg-[#1f2428] border-b-2 border-black dark:border-gray-600 font-mono text-xs font-bold text-gray-300 select-none\">\n    \u003Cdiv class=\"flex items-center gap-2\">\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ff5f56] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ffbd2e] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#27c93f] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"ml-2 font-mono font-bold text-xs uppercase tracking-wider text-gray-300\">TEXT\u003C\u002Fspan>\n    \u003C\u002Fdiv>\n    \u003Cbutton type=\"button\" class=\"copy-code-btn flex items-center gap-1.5 px-3 py-1 text-xs font-bold bg-[#2f363d] text-gray-200 border-2 border-black dark:border-gray-500 rounded-lg shadow-neo-sm hover:translate-x-0.5 hover:translate-y-0.5 hover:shadow-none hover:bg-gray-700 transition-all cursor-pointer\" data-code=\"ani.balance%20150%0Abudi.balance%2020%0Aani.history%20%5B'Ani%20deposit%2050'%2C%20'Budi%20deposit%2020'%5D%0Abudi.history%20%5B'Ani%20deposit%2050'%2C%20'Budi%20deposit%2020'%5D%0Asame%20list%3A%20True%0AAccount.history%20%5B'Ani%20deposit%2050'%2C%20'Budi%20deposit%2020'%5D%0Aani.__dict__%20%7B'owner'%3A%20'Ani'%2C%20'balance'%3A%20150%7D\" title=\"Salin kode\">\n      \u003Csvg class=\"w-3.5 h-3.5 copy-icon-svg\" fill=\"none\" stroke=\"currentColor\" viewBox=\"0 0 24 24\">\n        \u003Cpath stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\"2\" d=\"M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2-2h-8a2 2 0 00-2 2v8a2 2 0 002 2z\">\u003C\u002Fpath>\n      \u003C\u002Fsvg>\n      \u003Cspan class=\"copy-text\">Copy\u003C\u002Fspan>\n    \u003C\u002Fbutton>\n  \u003C\u002Fdiv>\n  \u003Cdiv class=\"code-block-content p-4 overflow-x-auto text-sm font-mono leading-relaxed bg-[#24292e]\">\n    \u003Cpre class=\"shiki github-dark\" style=\"background-color:#24292e;color:#e1e4e8\">\u003Ccode>ani.balance 150\nbudi.balance 20\nani.history ['Ani deposit 50', 'Budi deposit 20']\nbudi.history ['Ani deposit 50', 'Budi deposit 20']\nsame list: True\nAccount.history ['Ani deposit 50', 'Budi deposit 20']\nani.__dict__ {'owner': 'Ani', 'balance': 150}\u003C\u002Fcode>\u003C\u002Fpre>\n  \u003C\u002Fdiv>\n\u003C\u002Fdiv>\u003Cp>Read the last line. Ani's \u003Ccode>__dict__\u003C\u002Fcode> holds \u003Ccode>owner\u003C\u002Fcode> and \u003Ccode>balance\u003C\u002Fcode>, and no \u003Ccode>history\u003C\u002Fcode>. The attribute was never set on the object, so the lookup found the class's list.\u003C\u002Fp>\n\u003Cp>Reading \u003Ccode>self.history\u003C\u002Fcode> looks on the object first, then on the class. \u003Ccode>self.history.append(x)\u003C\u002Fcode> is a method call on whatever list that lookup returned. It is not an assignment, so nothing gets written to the object. The \u003Ca href=\"https:\u002F\u002Fdocs.python.org\u002F3\u002Ftutorial\u002Fclasses.html\">Python tutorial on classes\u003C\u002Fa> covers this lookup order.\u003C\u002Fp>\n\u003Ch2 id=\"two-files-one-command\">Two files, one command\u003C\u002Fh2>\n\u003Cp>Start with the broken version. The list sits in the class body, above \u003Ccode>__init__\u003C\u002Fcode>:\u003C\u002Fp>\n\n\u003Cdiv class=\"code-block-wrapper my-6 not-prose rounded-xl border-2 border-black dark:border-gray-600 shadow-neo overflow-hidden bg-[#24292e] text-[#e1e4e8] transition-all\">\n  \u003Cdiv class=\"code-block-header flex items-center justify-between px-4 py-2.5 bg-[#1f2428] border-b-2 border-black dark:border-gray-600 font-mono text-xs font-bold text-gray-300 select-none\">\n    \u003Cdiv class=\"flex items-center gap-2\">\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ff5f56] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ffbd2e] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#27c93f] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"ml-2 font-mono font-bold text-xs uppercase tracking-wider text-gray-300\">PYTHON\u003C\u002Fspan>\n    \u003C\u002Fdiv>\n    \u003Cbutton type=\"button\" class=\"copy-code-btn flex items-center gap-1.5 px-3 py-1 text-xs font-bold bg-[#2f363d] text-gray-200 border-2 border-black dark:border-gray-500 rounded-lg shadow-neo-sm hover:translate-x-0.5 hover:translate-y-0.5 hover:shadow-none hover:bg-gray-700 transition-all cursor-pointer\" data-code=\"%23%20account.py%0Aclass%20Account%3A%0A%20%20%20%20history%20%3D%20%5B%5D%0A%0A%20%20%20%20def%20__init__(self%2C%20owner%2C%20balance%3D0)%3A%0A%20%20%20%20%20%20%20%20self.owner%20%3D%20owner%0A%20%20%20%20%20%20%20%20self.balance%20%3D%20balance%0A%0A%20%20%20%20def%20deposit(self%2C%20amount)%3A%0A%20%20%20%20%20%20%20%20self.balance%20%3D%20self.balance%20%2B%20amount%0A%20%20%20%20%20%20%20%20self.history.append(f%22%7Bself.owner%7D%20deposit%20%7Bamount%7D%22)\" title=\"Salin kode\">\n      \u003Csvg class=\"w-3.5 h-3.5 copy-icon-svg\" fill=\"none\" stroke=\"currentColor\" viewBox=\"0 0 24 24\">\n        \u003Cpath stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\"2\" d=\"M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2-2h-8a2 2 0 00-2 2v8a2 2 0 002 2z\">\u003C\u002Fpath>\n      \u003C\u002Fsvg>\n      \u003Cspan class=\"copy-text\">Copy\u003C\u002Fspan>\n    \u003C\u002Fbutton>\n  \u003C\u002Fdiv>\n  \u003Cdiv class=\"code-block-content p-4 overflow-x-auto text-sm font-mono leading-relaxed bg-[#24292e]\">\n    \u003Cpre class=\"shiki github-dark\" style=\"background-color:#24292e;color:#e1e4e8\" tabindex=\"0\">\u003Ccode>\u003Cspan class=\"line\">\u003Cspan style=\"color:#6A737D\"># account.py\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">class\u003C\u002Fspan>\u003Cspan style=\"color:#B392F0\"> Account\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">:\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">    history \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> []\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">    def\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> __init__\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(self, owner, balance\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">0\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">):\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.owner \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> owner\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.balance \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> balance\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">    def\u003C\u002Fspan>\u003Cspan style=\"color:#B392F0\"> deposit\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(self, amount):\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.balance \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.balance \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">+\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> amount\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.history.append(\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">f\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.owner\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\"> deposit \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">amount\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\u003C\u002Fcode>\u003C\u002Fpre>\n  \u003C\u002Fdiv>\n\u003C\u002Fdiv>\u003Cp>Next, a checker. It builds two accounts, makes one deposit in each, and asks four questions:\u003C\u002Fp>\n\n\u003Cdiv class=\"code-block-wrapper my-6 not-prose rounded-xl border-2 border-black dark:border-gray-600 shadow-neo overflow-hidden bg-[#24292e] text-[#e1e4e8] transition-all\">\n  \u003Cdiv class=\"code-block-header flex items-center justify-between px-4 py-2.5 bg-[#1f2428] border-b-2 border-black dark:border-gray-600 font-mono text-xs font-bold text-gray-300 select-none\">\n    \u003Cdiv class=\"flex items-center gap-2\">\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ff5f56] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ffbd2e] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#27c93f] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"ml-2 font-mono font-bold text-xs uppercase tracking-wider text-gray-300\">PYTHON\u003C\u002Fspan>\n    \u003C\u002Fdiv>\n    \u003Cbutton type=\"button\" class=\"copy-code-btn flex items-center gap-1.5 px-3 py-1 text-xs font-bold bg-[#2f363d] text-gray-200 border-2 border-black dark:border-gray-500 rounded-lg shadow-neo-sm hover:translate-x-0.5 hover:translate-y-0.5 hover:shadow-none hover:bg-gray-700 transition-all cursor-pointer\" data-code=\"%23%20check_account.py%0Aimport%20account%0A%0Apassed%20%3D%200%0Atotal%20%3D%200%0A%0A%0Adef%20check(name%2C%20ok%2C%20detail%3D%22%22)%3A%0A%20%20%20%20global%20passed%2C%20total%0A%20%20%20%20total%20%2B%3D%201%0A%20%20%20%20if%20ok%3A%0A%20%20%20%20%20%20%20%20passed%20%2B%3D%201%0A%20%20%20%20%20%20%20%20print(f%22PASS%20%20%7Bname%7D%22)%0A%20%20%20%20else%3A%0A%20%20%20%20%20%20%20%20print(f%22FAIL%20%20%7Bname%7D%20%20%3C-%20%7Bdetail%7D%22)%0A%0A%0Aani%20%3D%20account.Account(%22Ani%22%2C%20100)%0Abudi%20%3D%20account.Account(%22Budi%22%2C%200)%0A%0Aani.deposit(50)%0Abudi.deposit(20)%0A%0Acheck(%22a%20deposit%20lands%20in%20the%20account%20that%20made%20it%22%2C%20ani.balance%20%3D%3D%20150%2C%20f%22balance%20is%20%7Bani.balance%7D%22)%0Acheck(%22the%20other%20account's%20balance%20does%20not%20move%22%2C%20budi.balance%20%3D%3D%2020%2C%20f%22balance%20is%20%7Bbudi.balance%7D%22)%0Acheck(%0A%20%20%20%20%22each%20account%20has%20one%20line%20of%20history%22%2C%0A%20%20%20%20len(ani.history)%20%3D%3D%201%20and%20len(budi.history)%20%3D%3D%201%2C%0A%20%20%20%20f%22ani%20has%20%7Blen(ani.history)%7D%2C%20budi%20has%20%7Blen(budi.history)%7D%22%2C%0A)%0Acheck(%0A%20%20%20%20%22the%20two%20history%20lists%20are%20different%20lists%22%2C%0A%20%20%20%20ani.history%20is%20not%20budi.history%2C%0A%20%20%20%20%22both%20accounts%20point%20at%20the%20same%20list%22%2C%0A)%0A%0Aprint()%0Aprint(f%22%7Bpassed%7D%20of%20%7Btotal%7D%20checks%20passed%22)%0Araise%20SystemExit(0%20if%20passed%20%3D%3D%20total%20else%201)\" title=\"Salin kode\">\n      \u003Csvg class=\"w-3.5 h-3.5 copy-icon-svg\" fill=\"none\" stroke=\"currentColor\" viewBox=\"0 0 24 24\">\n        \u003Cpath stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\"2\" d=\"M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2-2h-8a2 2 0 00-2 2v8a2 2 0 002 2z\">\u003C\u002Fpath>\n      \u003C\u002Fsvg>\n      \u003Cspan class=\"copy-text\">Copy\u003C\u002Fspan>\n    \u003C\u002Fbutton>\n  \u003C\u002Fdiv>\n  \u003Cdiv class=\"code-block-content p-4 overflow-x-auto text-sm font-mono leading-relaxed bg-[#24292e]\">\n    \u003Cpre class=\"shiki github-dark\" style=\"background-color:#24292e;color:#e1e4e8\" tabindex=\"0\">\u003Ccode>\u003Cspan class=\"line\">\u003Cspan style=\"color:#6A737D\"># check_account.py\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">import\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> account\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">passed \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> 0\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">total \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> 0\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">def\u003C\u002Fspan>\u003Cspan style=\"color:#B392F0\"> check\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(name, ok, detail\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">):\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">    global\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> passed, total\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">    total \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">+=\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> 1\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">    if\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> ok:\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">        passed \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">+=\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> 1\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        print\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">f\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"PASS  \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">name\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">    else\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">:\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        print\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">f\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"FAIL  \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">name\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">  <- \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">detail\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">ani \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> account.Account(\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"Ani\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">, \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">100\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">budi \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> account.Account(\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"Budi\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">, \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">0\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">ani.deposit(\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">50\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">budi.deposit(\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">20\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">check(\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"a deposit lands in the account that made it\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">, ani.balance \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">==\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> 150\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">, \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">f\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"balance is \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">ani.balance\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">check(\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"the other account's balance does not move\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">, budi.balance \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">==\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> 20\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">, \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">f\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"balance is \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">budi.balance\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">check(\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#9ECBFF\">    \"each account has one line of history\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">,\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">    len\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(ani.history) \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">==\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> 1\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\"> and\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> len\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(budi.history) \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">==\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> 1\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">,\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">    f\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"ani has \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{len\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(ani.history)\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">, budi has \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{len\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(budi.history)\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">,\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">check(\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#9ECBFF\">    \"the two history lists are different lists\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">,\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">    ani.history \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">is\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\"> not\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> budi.history,\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#9ECBFF\">    \"both accounts point at the same list\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">,\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">print\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">()\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">print\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">f\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">passed\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\"> of \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">total\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\"> checks passed\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">raise\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> SystemExit\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">0\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\"> if\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> passed \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">==\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> total \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">else\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> 1\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\u003C\u002Fcode>\u003C\u002Fpre>\n  \u003C\u002Fdiv>\n\u003C\u002Fdiv>\u003Cp>Run \u003Ccode>python3 check_account.py\u003C\u002Fcode> with the starter in place. It exits with code 1:\u003C\u002Fp>\n\n\u003Cdiv class=\"code-block-wrapper my-6 not-prose rounded-xl border-2 border-black dark:border-gray-600 shadow-neo overflow-hidden bg-[#24292e] text-[#e1e4e8] transition-all\">\n  \u003Cdiv class=\"code-block-header flex items-center justify-between px-4 py-2.5 bg-[#1f2428] border-b-2 border-black dark:border-gray-600 font-mono text-xs font-bold text-gray-300 select-none\">\n    \u003Cdiv class=\"flex items-center gap-2\">\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ff5f56] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ffbd2e] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#27c93f] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"ml-2 font-mono font-bold text-xs uppercase tracking-wider text-gray-300\">TEXT\u003C\u002Fspan>\n    \u003C\u002Fdiv>\n    \u003Cbutton type=\"button\" class=\"copy-code-btn flex items-center gap-1.5 px-3 py-1 text-xs font-bold bg-[#2f363d] text-gray-200 border-2 border-black dark:border-gray-500 rounded-lg shadow-neo-sm hover:translate-x-0.5 hover:translate-y-0.5 hover:shadow-none hover:bg-gray-700 transition-all cursor-pointer\" data-code=\"PASS%20%20a%20deposit%20lands%20in%20the%20account%20that%20made%20it%0APASS%20%20the%20other%20account's%20balance%20does%20not%20move%0AFAIL%20%20each%20account%20has%20one%20line%20of%20history%20%20%3C-%20ani%20has%202%2C%20budi%20has%202%0AFAIL%20%20the%20two%20history%20lists%20are%20different%20lists%20%20%3C-%20both%20accounts%20point%20at%20the%20same%20list%0A%0A2%20of%204%20checks%20passed\" title=\"Salin kode\">\n      \u003Csvg class=\"w-3.5 h-3.5 copy-icon-svg\" fill=\"none\" stroke=\"currentColor\" viewBox=\"0 0 24 24\">\n        \u003Cpath stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\"2\" d=\"M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2-2h-8a2 2 0 00-2 2v8a2 2 0 002 2z\">\u003C\u002Fpath>\n      \u003C\u002Fsvg>\n      \u003Cspan class=\"copy-text\">Copy\u003C\u002Fspan>\n    \u003C\u002Fbutton>\n  \u003C\u002Fdiv>\n  \u003Cdiv class=\"code-block-content p-4 overflow-x-auto text-sm font-mono leading-relaxed bg-[#24292e]\">\n    \u003Cpre class=\"shiki github-dark\" style=\"background-color:#24292e;color:#e1e4e8\">\u003Ccode>PASS  a deposit lands in the account that made it\nPASS  the other account's balance does not move\nFAIL  each account has one line of history  <- ani has 2, budi has 2\nFAIL  the two history lists are different lists  <- both accounts point at the same list\n\n2 of 4 checks passed\u003C\u002Fcode>\u003C\u002Fpre>\n  \u003C\u002Fdiv>\n\u003C\u002Fdiv>\u003Cp>Two checks already pass, and that is the trap. \u003Ccode>self.balance = ...\u003C\u002Fcode> is an assignment, and assignment always writes on the object, so each account gets its own \u003Ccode>balance\u003C\u002Fcode>. \u003Ccode>self.history.append(...)\u003C\u002Fcode> never assigns anything. Balances are the first thing you would test, and they look fine.\u003C\u002Fp>\n\u003Cp>Now move the list into \u003Ccode>__init__\u003C\u002Fcode>, so each object creates its own:\u003C\u002Fp>\n\n\u003Cdiv class=\"code-block-wrapper my-6 not-prose rounded-xl border-2 border-black dark:border-gray-600 shadow-neo overflow-hidden bg-[#24292e] text-[#e1e4e8] transition-all\">\n  \u003Cdiv class=\"code-block-header flex items-center justify-between px-4 py-2.5 bg-[#1f2428] border-b-2 border-black dark:border-gray-600 font-mono text-xs font-bold text-gray-300 select-none\">\n    \u003Cdiv class=\"flex items-center gap-2\">\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ff5f56] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ffbd2e] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#27c93f] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"ml-2 font-mono font-bold text-xs uppercase tracking-wider text-gray-300\">PYTHON\u003C\u002Fspan>\n    \u003C\u002Fdiv>\n    \u003Cbutton type=\"button\" class=\"copy-code-btn flex items-center gap-1.5 px-3 py-1 text-xs font-bold bg-[#2f363d] text-gray-200 border-2 border-black dark:border-gray-500 rounded-lg shadow-neo-sm hover:translate-x-0.5 hover:translate-y-0.5 hover:shadow-none hover:bg-gray-700 transition-all cursor-pointer\" data-code=\"%23%20account.py%0Aclass%20Account%3A%0A%20%20%20%20def%20__init__(self%2C%20owner%2C%20balance%3D0)%3A%0A%20%20%20%20%20%20%20%20self.owner%20%3D%20owner%0A%20%20%20%20%20%20%20%20self.balance%20%3D%20balance%0A%20%20%20%20%20%20%20%20self.history%20%3D%20%5B%5D%0A%0A%20%20%20%20def%20deposit(self%2C%20amount)%3A%0A%20%20%20%20%20%20%20%20self.balance%20%3D%20self.balance%20%2B%20amount%0A%20%20%20%20%20%20%20%20self.history.append(f%22%7Bself.owner%7D%20deposit%20%7Bamount%7D%22)\" title=\"Salin kode\">\n      \u003Csvg class=\"w-3.5 h-3.5 copy-icon-svg\" fill=\"none\" stroke=\"currentColor\" viewBox=\"0 0 24 24\">\n        \u003Cpath stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\"2\" d=\"M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2-2h-8a2 2 0 00-2 2v8a2 2 0 002 2z\">\u003C\u002Fpath>\n      \u003C\u002Fsvg>\n      \u003Cspan class=\"copy-text\">Copy\u003C\u002Fspan>\n    \u003C\u002Fbutton>\n  \u003C\u002Fdiv>\n  \u003Cdiv class=\"code-block-content p-4 overflow-x-auto text-sm font-mono leading-relaxed bg-[#24292e]\">\n    \u003Cpre class=\"shiki github-dark\" style=\"background-color:#24292e;color:#e1e4e8\" tabindex=\"0\">\u003Ccode>\u003Cspan class=\"line\">\u003Cspan style=\"color:#6A737D\"># account.py\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">class\u003C\u002Fspan>\u003Cspan style=\"color:#B392F0\"> Account\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">:\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">    def\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> __init__\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(self, owner, balance\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">0\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">):\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.owner \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> owner\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.balance \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> balance\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.history \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> []\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#F97583\">    def\u003C\u002Fspan>\u003Cspan style=\"color:#B392F0\"> deposit\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">(self, amount):\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.balance \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\"> self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.balance \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">+\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> amount\u003C\u002Fspan>\u003C\u002Fspan>\n\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">        self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.history.append(\u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">f\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.owner\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\"> deposit \u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">{\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">amount\u003C\u002Fspan>\u003Cspan style=\"color:#79B8FF\">}\u003C\u002Fspan>\u003Cspan style=\"color:#9ECBFF\">\"\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">)\u003C\u002Fspan>\u003C\u002Fspan>\u003C\u002Fcode>\u003C\u002Fpre>\n  \u003C\u002Fdiv>\n\u003C\u002Fdiv>\u003Cp>Run the same command again. This time it exits with code 0:\u003C\u002Fp>\n\n\u003Cdiv class=\"code-block-wrapper my-6 not-prose rounded-xl border-2 border-black dark:border-gray-600 shadow-neo overflow-hidden bg-[#24292e] text-[#e1e4e8] transition-all\">\n  \u003Cdiv class=\"code-block-header flex items-center justify-between px-4 py-2.5 bg-[#1f2428] border-b-2 border-black dark:border-gray-600 font-mono text-xs font-bold text-gray-300 select-none\">\n    \u003Cdiv class=\"flex items-center gap-2\">\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ff5f56] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ffbd2e] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#27c93f] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"ml-2 font-mono font-bold text-xs uppercase tracking-wider text-gray-300\">TEXT\u003C\u002Fspan>\n    \u003C\u002Fdiv>\n    \u003Cbutton type=\"button\" class=\"copy-code-btn flex items-center gap-1.5 px-3 py-1 text-xs font-bold bg-[#2f363d] text-gray-200 border-2 border-black dark:border-gray-500 rounded-lg shadow-neo-sm hover:translate-x-0.5 hover:translate-y-0.5 hover:shadow-none hover:bg-gray-700 transition-all cursor-pointer\" data-code=\"PASS%20%20a%20deposit%20lands%20in%20the%20account%20that%20made%20it%0APASS%20%20the%20other%20account's%20balance%20does%20not%20move%0APASS%20%20each%20account%20has%20one%20line%20of%20history%0APASS%20%20the%20two%20history%20lists%20are%20different%20lists%0A%0A4%20of%204%20checks%20passed\" title=\"Salin kode\">\n      \u003Csvg class=\"w-3.5 h-3.5 copy-icon-svg\" fill=\"none\" stroke=\"currentColor\" viewBox=\"0 0 24 24\">\n        \u003Cpath stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\"2\" d=\"M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2-2h-8a2 2 0 00-2 2v8a2 2 0 002 2z\">\u003C\u002Fpath>\n      \u003C\u002Fsvg>\n      \u003Cspan class=\"copy-text\">Copy\u003C\u002Fspan>\n    \u003C\u002Fbutton>\n  \u003C\u002Fdiv>\n  \u003Cdiv class=\"code-block-content p-4 overflow-x-auto text-sm font-mono leading-relaxed bg-[#24292e]\">\n    \u003Cpre class=\"shiki github-dark\" style=\"background-color:#24292e;color:#e1e4e8\">\u003Ccode>PASS  a deposit lands in the account that made it\nPASS  the other account's balance does not move\nPASS  each account has one line of history\nPASS  the two history lists are different lists\n\n4 of 4 checks passed\u003C\u002Fcode>\u003C\u002Fpre>\n  \u003C\u002Fdiv>\n\u003C\u002Fdiv>\u003Cp>I ran all of this on Python 3.14.9 on Linux. I did not try other Python versions, so this is the evidence from one machine.\u003C\u002Fp>\n\u003Ch2 id=\"what-this-does-not-do\">What this does not do\u003C\u002Fh2>\n\u003Cp>A class attribute is still the right home for a value nobody mutates. The checker cannot tell a shared constant from a shared list, and it should not. Sharing was never the problem. Mutating something shared was.\u003C\u002Fp>\n\u003Cp>An empty \u003Ccode>history\u003C\u002Fcode> is also not proof that you fixed it. Every account starts with an empty list in both versions. The bug only shows once a second object exists, which is exactly what the checker builds.\u003C\u002Fp>\n\u003Ch2 id=\"break-it-on-purpose\">Break it on purpose\u003C\u002Fh2>\n\u003Cp>Put \u003Ccode>history = []\u003C\u002Fcode> back in the class body. Then add one line to \u003Ccode>__init__\u003C\u002Fcode>:\u003C\u002Fp>\n\n\u003Cdiv class=\"code-block-wrapper my-6 not-prose rounded-xl border-2 border-black dark:border-gray-600 shadow-neo overflow-hidden bg-[#24292e] text-[#e1e4e8] transition-all\">\n  \u003Cdiv class=\"code-block-header flex items-center justify-between px-4 py-2.5 bg-[#1f2428] border-b-2 border-black dark:border-gray-600 font-mono text-xs font-bold text-gray-300 select-none\">\n    \u003Cdiv class=\"flex items-center gap-2\">\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ff5f56] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ffbd2e] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#27c93f] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"ml-2 font-mono font-bold text-xs uppercase tracking-wider text-gray-300\">PYTHON\u003C\u002Fspan>\n    \u003C\u002Fdiv>\n    \u003Cbutton type=\"button\" class=\"copy-code-btn flex items-center gap-1.5 px-3 py-1 text-xs font-bold bg-[#2f363d] text-gray-200 border-2 border-black dark:border-gray-500 rounded-lg shadow-neo-sm hover:translate-x-0.5 hover:translate-y-0.5 hover:shadow-none hover:bg-gray-700 transition-all cursor-pointer\" data-code=\"self.history%20%3D%20Account.history\" title=\"Salin kode\">\n      \u003Csvg class=\"w-3.5 h-3.5 copy-icon-svg\" fill=\"none\" stroke=\"currentColor\" viewBox=\"0 0 24 24\">\n        \u003Cpath stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\"2\" d=\"M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2-2h-8a2 2 0 00-2 2v8a2 2 0 002 2z\">\u003C\u002Fpath>\n      \u003C\u002Fsvg>\n      \u003Cspan class=\"copy-text\">Copy\u003C\u002Fspan>\n    \u003C\u002Fbutton>\n  \u003C\u002Fdiv>\n  \u003Cdiv class=\"code-block-content p-4 overflow-x-auto text-sm font-mono leading-relaxed bg-[#24292e]\">\n    \u003Cpre class=\"shiki github-dark\" style=\"background-color:#24292e;color:#e1e4e8\" tabindex=\"0\">\u003Ccode>\u003Cspan class=\"line\">\u003Cspan style=\"color:#79B8FF\">self\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\">.history \u003C\u002Fspan>\u003Cspan style=\"color:#F97583\">=\u003C\u002Fspan>\u003Cspan style=\"color:#E1E4E8\"> Account.history\u003C\u002Fspan>\u003C\u002Fspan>\u003C\u002Fcode>\u003C\u002Fpre>\n  \u003C\u002Fdiv>\n\u003C\u002Fdiv>\u003Cp>It looks like each account now gets its own list. Run the checker and two checks fail again:\u003C\u002Fp>\n\n\u003Cdiv class=\"code-block-wrapper my-6 not-prose rounded-xl border-2 border-black dark:border-gray-600 shadow-neo overflow-hidden bg-[#24292e] text-[#e1e4e8] transition-all\">\n  \u003Cdiv class=\"code-block-header flex items-center justify-between px-4 py-2.5 bg-[#1f2428] border-b-2 border-black dark:border-gray-600 font-mono text-xs font-bold text-gray-300 select-none\">\n    \u003Cdiv class=\"flex items-center gap-2\">\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ff5f56] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#ffbd2e] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"w-3 h-3 rounded-full bg-[#27c93f] border border-black\u002F40 inline-block\">\u003C\u002Fspan>\n      \u003Cspan class=\"ml-2 font-mono font-bold text-xs uppercase tracking-wider text-gray-300\">TEXT\u003C\u002Fspan>\n    \u003C\u002Fdiv>\n    \u003Cbutton type=\"button\" class=\"copy-code-btn flex items-center gap-1.5 px-3 py-1 text-xs font-bold bg-[#2f363d] text-gray-200 border-2 border-black dark:border-gray-500 rounded-lg shadow-neo-sm hover:translate-x-0.5 hover:translate-y-0.5 hover:shadow-none hover:bg-gray-700 transition-all cursor-pointer\" data-code=\"PASS%20%20a%20deposit%20lands%20in%20the%20account%20that%20made%20it%0APASS%20%20the%20other%20account's%20balance%20does%20not%20move%0AFAIL%20%20each%20account%20has%20one%20line%20of%20history%20%20%3C-%20ani%20has%202%2C%20budi%20has%202%0AFAIL%20%20the%20two%20history%20lists%20are%20different%20lists%20%20%3C-%20both%20accounts%20point%20at%20the%20same%20list%0A%0A2%20of%204%20checks%20passed\" title=\"Salin kode\">\n      \u003Csvg class=\"w-3.5 h-3.5 copy-icon-svg\" fill=\"none\" stroke=\"currentColor\" viewBox=\"0 0 24 24\">\n        \u003Cpath stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\"2\" d=\"M8 16H6a2 2 0 01-2-2V6a2 2 0 012-2h8a2 2 0 012 2v2m-6 12h8a2 2 0 002-2v-8a2 2 0 00-2-2h-8a2 2 0 00-2 2v8a2 2 0 002 2z\">\u003C\u002Fpath>\n      \u003C\u002Fsvg>\n      \u003Cspan class=\"copy-text\">Copy\u003C\u002Fspan>\n    \u003C\u002Fbutton>\n  \u003C\u002Fdiv>\n  \u003Cdiv class=\"code-block-content p-4 overflow-x-auto text-sm font-mono leading-relaxed bg-[#24292e]\">\n    \u003Cpre class=\"shiki github-dark\" style=\"background-color:#24292e;color:#e1e4e8\">\u003Ccode>PASS  a deposit lands in the account that made it\nPASS  the other account's balance does not move\nFAIL  each account has one line of history  <- ani has 2, budi has 2\nFAIL  the two history lists are different lists  <- both accounts point at the same list\n\n2 of 4 checks passed\u003C\u002Fcode>\u003C\u002Fpre>\n  \u003C\u002Fdiv>\n\u003C\u002Fdiv>\u003Cp>The new line copies the same list object into both objects, so the objects still share it.\u003C\u002Fp>\n\u003Cp>Before you put a list, dict, or set in a class body, ask one question: should a second object see this change? If yes, share it on purpose. If no, build it in \u003Ccode>__init__\u003C\u002Fcode>.\u003C\u002Fp>\n","\u003Cul>\n\u003Cli>A list assigned in the class body belongs to the class, so every object reads that same list until the object gets one of its own.\u003C\u002Fli>\n\u003Cli>\u003Ccode>self.history.append(x)\u003C\u002Fcode> reads the class attribute and mutates it; it never writes an attribute on the object, which is why \u003Ccode>history\u003C\u002Fcode> is absent from \u003Ccode>ani.__dict__\u003C\u002Fcode>.\u003C\u002Fli>\n\u003Cli>\u003Ccode>self.balance = ...\u003C\u002Fcode> looked correct because assignment always writes on the object that holds the name.\u003C\u002Fli>\n\u003Cli>Build mutable state in \u003Ccode>__init__\u003C\u002Fcode>, and leave a class attribute for values no object should be able to change.\u003C\u002Fli>\n\u003C\u002Ful>\n",[155,178,199,217,222,240],{"id":156,"title":157,"title_id":158,"slug":159,"excerpt":160,"excerpt_id":161,"has_translation":12,"published_at":162,"reading_time":163,"hidden_from_listing":15,"tags":164,"thumbnail_image":21,"og_image":169,"series":170,"authors":175},48,"What a Linked List Actually Is","Tentang Struktur Data LinkedList","tentang-struktur-data-linked-list","A linked list is a linear chain of nodes, each holding data and a pointer to the next node. Here is what that chain costs next to an array, plus a minimal implementation you can run.","Linked list adalah rantai linear berisi node, dan setiap node menyimpan data plus pointer ke node berikutnya. Ini ongkosnya dibanding array, plus implementasi paling sederhananya.","2026-11-21T01:00:00.000Z",3,[165,166,167,168],"struktur-data","linked-list","pointer","konsep","\u002Fog\u002Ftentang-struktur-data-linked-list.png",{"id":171,"title":172,"title_id":173,"slug":174},28,"Linear Data Structures","Struktur Data Linear","asd-struktur-linear",[176],{"authors_id":177},{"id":94,"name":95,"slug":96,"role":97,"profile_picture":21},{"id":179,"title":180,"title_id":181,"slug":182,"excerpt":183,"excerpt_id":184,"has_translation":12,"published_at":185,"reading_time":186,"hidden_from_listing":15,"tags":187,"thumbnail_image":21,"og_image":190,"series":191,"authors":196},47,"Why Understanding Algorithms and Data Structures Actually Matters","Pentingnya Memahami Algoritma dan Struktur Data","pentingnya-memahami-algoritma-dan-struktur-data","An algorithm is an ordered list of steps, and that order decides how expensive a problem is. The examples are on the back of an instant noodle packet, in a factorial, and behind ctrl+z.","Sebagai konsep fundamental, algoritma menentukan seberapa mahal sebuah masalah diselesaikan. Contohnya ada di bungkus mie instan, di bilangan faktorial, dan di tombol undo.","2026-11-19T01:00:00.000Z",7,[188,165,168,189],"algoritma","dasar","\u002Fog\u002Fpentingnya-memahami-algoritma-dan-struktur-data.png",{"id":192,"title":193,"title_id":194,"slug":195},27,"About Algorithms and Data Structures","Tentang Algoritma dan Struktur Data","asd-intro",[197],{"authors_id":198},{"id":94,"name":95,"slug":96,"role":97,"profile_picture":21},{"id":200,"title":201,"title_id":202,"slug":203,"excerpt":204,"excerpt_id":205,"has_translation":12,"published_at":206,"reading_time":14,"hidden_from_listing":15,"tags":207,"thumbnail_image":21,"og_image":212,"series":213,"authors":214},108,"At 11 a.m. the AI Quota Runs Out, and the Work Stops There","Jam 11 siang kuota AI-nya habis, dan kerjaan berhenti di situ","jam-11-kuota-ai-habis-kerjaan-berhenti","The panel says the usage limit is reached and the work stops, not because it is finished. Three guesses explain it, and all three are wrong: the limit is shaped like a cliff, and the day is built on top of one tool.","Panel di layar bilang batas pemakaian tercapai, dan kerja berhenti di situ. Bukan karena selesai. Ada tiga tebakan kenapa ini terjadi, dan ketiganya salah: batasnya berbentuk tebing, dan harinya dibangun di atas satu alat.","2026-11-12T01:00:00.000Z",[208,209,210,211],"ai","tooling","rate-limit","produktivitas","\u002Fog\u002Fjam-11-kuota-ai-habis-kerjaan-berhenti.png",{"id":24,"title":25,"title_id":26,"slug":27},[215],{"authors_id":216},{"id":94,"name":95,"slug":96,"role":97,"profile_picture":21},{"id":74,"title":75,"title_id":76,"slug":77,"excerpt":78,"excerpt_id":79,"has_translation":12,"published_at":80,"reading_time":14,"hidden_from_listing":15,"tags":81,"thumbnail_image":21,"og_image":84,"series":218,"authors":219},{"id":86,"title":52,"title_id":53,"slug":54},[220],{"authors_id":221},{"id":94,"name":95,"slug":96,"role":97,"profile_picture":21},{"id":223,"title":224,"title_id":225,"slug":226,"excerpt":227,"excerpt_id":228,"has_translation":12,"published_at":229,"reading_time":14,"hidden_from_listing":15,"tags":230,"thumbnail_image":21,"og_image":233,"series":234,"authors":237},137,"Java Operators: the Average That Came Out a Whole Number","Operator Java: Rata-Rata yang Keluar Sebagai Bilangan Bulat","java-operators","Three scores, one division, and the average prints as 82. Both operands are `int`, so the fraction is cut off, and the obvious cast prints `82.0` without fixing anything.","Tiga nilai, satu pembagian, dan rata-ratanya tercetak 82. Kedua operand-nya `int`, jadi pecahannya dipotong, dan cast yang paling wajar malah mencetak `82.0` tanpa memperbaiki apa pun.","2026-11-06T01:00:00.000Z",[231,232],"java","operator","\u002Fog\u002Fjava-operators.png",{"id":235,"title":107,"title_id":108,"slug":236},22,"java-variabel-tipe-data",[238],{"authors_id":239},{"id":94,"name":95,"slug":96,"role":97,"profile_picture":21},{"id":241,"title":242,"title_id":243,"slug":244,"excerpt":245,"excerpt_id":246,"has_translation":12,"published_at":229,"reading_time":186,"hidden_from_listing":15,"tags":247,"thumbnail_image":21,"og_image":249,"series":250,"authors":251},136,"Python Modules: the Import That Printed the Report","Modul Python: Import yang Mencetak Laporannya","python-modules","You pull one function out into its own file, import it, and the whole report runs again and eats your input. A module is a file, `import` runs it top to bottom, and one line decides which of the two jobs it is doing.","Kamu memindahkan satu fungsi ke file sendiri, meng-import-nya, dan seluruh laporan jalan lagi lalu memakan inputmu. Modul adalah file, `import` menjalankannya dari atas ke bawah, dan satu baris menentukan pekerjaan mana yang sedang dijalankan file itu.",[82,248],"modules","\u002Fog\u002Fpython-modules.png",{"id":112,"title":113,"title_id":114,"slug":115},[252],{"authors_id":253},{"id":94,"name":95,"slug":96,"role":97,"profile_picture":21},[255,259,262],{"text":256,"depth":257,"id":258},"Two files, one command",2,"two-files-one-command",{"text":260,"depth":257,"id":261},"What this does not do","what-this-does-not-do",{"text":263,"depth":257,"id":264},"Break it on purpose","break-it-on-purpose",1794029330825]