{"id":3383,"date":"2026-09-08T10:45:32","date_gmt":"2026-09-08T01:45:32","guid":{"rendered":"https:\/\/qol-kk.com\/wp2\/?p=3383"},"modified":"2026-09-08T10:45:32","modified_gmt":"2026-09-08T01:45:32","slug":"20260908-plan023","status":"publish","type":"post","link":"https:\/\/qol-kk.com\/wp2\/blog\/2026\/09\/08\/20260908-plan023\/","title":{"rendered":"Python \u306e\u578b\u30d2\u30f3\u30c8\u5165\u9580 \u2014 \u57fa\u672c\u578b\u304b\u3089\u30b8\u30a7\u30cd\u30ea\u30af\u30b9\u307e\u3067"},"content":{"rendered":"<h2>\u6982\u8981<\/h2>\n<p>Python \u306f\u52d5\u7684\u578b\u4ed8\u3051\u8a00\u8a9e\u3067\u3059\u304c\u30013.5 \u4ee5\u964d\u3067\u5c0e\u5165\u3055\u308c\u305f\u300c\u578b\u30d2\u30f3\u30c8\uff08type hints\uff09\u300d\u3092\u4f7f\u3046\u3068\u3001\u95a2\u6570\u3084\u5909\u6570\u306b\u671f\u5f85\u3059\u308b\u578b\u3092\u6ce8\u91c8\u3068\u3057\u3066\u66f8\u3051\u307e\u3059\u3002\u578b\u30d2\u30f3\u30c8\u306f\u5b9f\u884c\u6642\u306b\u306f\u57fa\u672c\u7684\u306b\u7121\u8996\u3055\u308c\u307e\u3059\u304c\u3001<code>mypy<\/code> \u306a\u3069\u306e\u9759\u7684\u89e3\u6790\u30c4\u30fc\u30eb\u3084\u30a8\u30c7\u30a3\u30bf\u306e\u88dc\u5b8c\u30fb\u8b66\u544a\u306b\u6d3b\u7528\u3067\u304d\u3001\u5927\u898f\u6a21\u5316\u3057\u305f\u30b3\u30fc\u30c9\u306e\u5b89\u5168\u6027\u3068\u53ef\u8aad\u6027\u3092\u5927\u304d\u304f\u6539\u5584\u3057\u307e\u3059\u3002<\/p>\n<p>\u3053\u306e\u8a18\u4e8b\u3067\u306f\u3001\u57fa\u672c\u578b\u306e\u6ce8\u91c8\u304b\u3089 <code>Optional<\/code>\u30fb<code>Union<\/code>\u3001\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u578b\u3001\u305d\u3057\u3066\u30b8\u30a7\u30cd\u30ea\u30af\u30b9\uff08\u7dcf\u79f0\u578b\uff09\u307e\u3067\u3092\u3001\u52d5\u304f\u6700\u5c0f\u30b3\u30fc\u30c9\u3068\u3068\u3082\u306b\u9806\u3092\u8ffd\u3063\u3066\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n<h2>\u74b0\u5883<\/h2>\n<ul>\n<li>Python 3.10 \u4ee5\u964d\uff08\u65b0\u8a18\u6cd5 <code>X | Y<\/code> \u3084 <code>list[int]<\/code> \u3092\u524d\u63d0\uff09<\/li>\n<li>\u578b\u30c1\u30a7\u30c3\u30ab\u30fc: <code>mypy<\/code>\uff08<code>pip install mypy<\/code>\uff09<\/li>\n<\/ul>\n<pre class=\"lang:default decode:true\">python --version\n# Python 3.11.x\npip install mypy\nmypy your_script.py<\/pre>\n<p>3.9 \u4ee5\u524d\u3067\u306f\u4e00\u90e8\u306e\u8a18\u6cd5\u304c\u4f7f\u3048\u306a\u3044\u305f\u3081\u3001<code>from __future__ import annotations<\/code> \u3084 <code>typing<\/code> \u30e2\u30b8\u30e5\u30fc\u30eb\u3067\u4ee3\u66ff\u3057\u307e\u3059\u3002<\/p>\n<h2>\u578b\u30d2\u30f3\u30c8\u306f\u5b9f\u884c\u6642\u306b\u306f\u52b9\u304b\u306a\u3044<\/h2>\n<p>\u6700\u521d\u306b\u62bc\u3055\u3048\u308b\u3079\u304d\u6700\u91cd\u8981\u30dd\u30a4\u30f3\u30c8\u3067\u3059\u3002\u578b\u30d2\u30f3\u30c8\u306f\u5b9f\u884c\u6642\u306e\u6319\u52d5\u3092\u5909\u3048\u307e\u305b\u3093\u3002<\/p>\n<pre class=\"lang:default decode:true\">def add(a: int, b: int) -&gt; int:\n    return a + b\n\n# \u5b9f\u884c\u6642\u306b\u306f\u578b\u30c1\u30a7\u30c3\u30af\u3055\u308c\u306a\u3044\u305f\u3081\u3001\u3053\u308c\u306f\u52d5\u3044\u3066\u3057\u307e\u3046\nprint(add(\"x\", \"y\"))  # -&gt; \"xy\"<\/pre>\n<p>\u3053\u306e\u30b3\u30fc\u30c9\u306f\u5b9f\u884c\u3059\u308b\u3068\u30a8\u30e9\u30fc\u306b\u306a\u308a\u307e\u305b\u3093\u304c\u3001<code>mypy<\/code> \u306b\u304b\u3051\u308b\u3068\u578b\u306e\u4e0d\u4e00\u81f4\u3068\u3057\u3066\u8b66\u544a\u3055\u308c\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">$ mypy sample.py\nsample.py:5: error: Argument 1 to \"add\" has incompatible type \"str\"; expected \"int\"  [arg-type]<\/pre>\n<p>\u3064\u307e\u308a\u578b\u30d2\u30f3\u30c8\u306f\u300c\u5b9f\u884c\u3092\u6b62\u3081\u308b\u4ed5\u7d44\u307f\u300d\u3067\u306f\u306a\u304f\u300c\u9759\u7684\u89e3\u6790\u3068\u30c4\u30fc\u30eb\u652f\u63f4\u306e\u305f\u3081\u306e\u60c5\u5831\u300d\u3067\u3059\u3002<\/p>\n<h2>\u57fa\u672c\u578b\u306e\u6ce8\u91c8<\/h2>\n<pre class=\"lang:default decode:true\">name: str = \"Alice\"\nage: int = 30\nheight: float = 165.5\nis_admin: bool = False\n\ndef greet(name: str) -&gt; str:\n    return f\"Hello, {name}\"\n\ndef log(message: str) -&gt; None:  # \u623b\u308a\u5024\u304c\u306a\u3044\u95a2\u6570\u306f None\n    print(message)<\/pre>\n<h2>Optional \u3068 Union<\/h2>\n<p>\u5024\u304c\u300c\u3042\u308b\u578b \u307e\u305f\u306f None\u300d\u306b\u306a\u308a\u5f97\u308b\u5834\u5408\u306f <code>Optional<\/code> \u3092\u4f7f\u3044\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">from typing import Optional\n\ndef find_user(user_id: int) -&gt; Optional[str]:\n    users = {1: \"Alice\", 2: \"Bob\"}\n    return users.get(user_id)  # \u898b\u3064\u304b\u3089\u306a\u3051\u308c\u3070 None<\/pre>\n<p><code>Optional[str]<\/code> \u306f <code>str | None<\/code> \u3068\u540c\u7fa9\u3067\u3059\u3002Python 3.10 \u4ee5\u964d\u306a\u3089\u65b0\u8a18\u6cd5\u304c\u8aad\u307f\u3084\u3059\u3044\u3067\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">def show(user: str | None) -&gt; None:\n    if user is None:\n        print(\"not found\")\n        return\n    # \u3053\u3053\u3067\u306f user \u306f str \u306b\u7d5e\u308a\u8fbc\u307e\u308c\u3066\u3044\u308b\uff08\u578b\u30ca\u30ed\u30fc\u30a4\u30f3\u30b0\uff09\n    print(user.upper())<\/pre>\n<p>\u8907\u6570\u306e\u578b\u3092\u53d6\u308a\u5f97\u308b\u5834\u5408\u306f <code>Union<\/code>\uff08\u65b0\u8a18\u6cd5 <code>|<\/code>\uff09\u3092\u4f7f\u3044\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">def to_int(value: int | str) -&gt; int:\n    return int(value)<\/pre>\n<h2>\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u578b<\/h2>\n<p>\u30ea\u30b9\u30c8\u3084\u8f9e\u66f8\u306b\u306f\u8981\u7d20\u306e\u578b\u307e\u3067\u66f8\u3051\u307e\u3059\u30023.9 \u4ee5\u964d\u306f\u7d44\u307f\u8fbc\u307f\u578b\u3092\u305d\u306e\u307e\u307e\u4f7f\u3048\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">scores: list[int] = [90, 85, 100]\nuser_map: dict[int, str] = {1: \"Alice\", 2: \"Bob\"}\npoint: tuple[int, int] = (10, 20)\ntags: set[str] = {\"python\", \"typing\"}\n\ndef group_by_len(words: list[str]) -&gt; dict[int, list[str]]:\n    result: dict[int, list[str]] = {}\n    for w in words:\n        result.setdefault(len(w), []).append(w)\n    return result<\/pre>\n<p>\u8aad\u307f\u53d6\u308a\u5c02\u7528\u3067\u6c4e\u7528\u7684\u306b\u53d7\u3051\u305f\u3044\u5834\u5408\u306f\u3001<code>list<\/code> \u3088\u308a\u62bd\u8c61\u7684\u306a <code>Iterable<\/code> \/ <code>Sequence<\/code> \u304c\u4fbf\u5229\u3067\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">from collections.abc import Iterable\n\ndef total(scores: Iterable[int]) -&gt; int:  # list \u3067\u3082 tuple \u3067\u3082\u53d7\u3051\u3089\u308c\u308b\n    return sum(scores)<\/pre>\n<h2>\u30b8\u30a7\u30cd\u30ea\u30af\u30b9\uff08\u7dcf\u79f0\u578b\uff09<\/h2>\n<p>\u30b8\u30a7\u30cd\u30ea\u30af\u30b9\u306f\u300c\u578b\u3092\u5f15\u6570\u3068\u3057\u3066\u53d7\u3051\u53d6\u308b\u300d\u4ed5\u7d44\u307f\u3067\u3001\u8981\u7d20\u306e\u578b\u304c\u547c\u3073\u51fa\u3057\u5074\u3067\u6c7a\u307e\u308b\u6c4e\u7528\u95a2\u6570\u30fb\u30af\u30e9\u30b9\u3092\u578b\u5b89\u5168\u306b\u66f8\u3051\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">from typing import TypeVar\n\nT = TypeVar(\"T\")\n\ndef first(items: list[T]) -&gt; T:\n    return items[0]\n\nn = first([1, 2, 3])   # n \u306f int \u3068\u63a8\u8ad6\u3055\u308c\u308b\ns = first([\"a\", \"b\"])  # s \u306f str \u3068\u63a8\u8ad6\u3055\u308c\u308b<\/pre>\n<p><code>Any<\/code> \u3092\u4f7f\u3046\u3068\u578b\u60c5\u5831\u304c\u5931\u308f\u308c\u307e\u3059\u304c\u3001<code>TypeVar<\/code> \u306a\u3089\u5165\u51fa\u529b\u306e\u578b\u304c\u3064\u306a\u304c\u308a\u307e\u3059\u3002<\/p>\n<h3>\u30b8\u30a7\u30cd\u30ea\u30c3\u30af\u30af\u30e9\u30b9\uff083.12 \u4ee5\u964d\u306e\u65b0\u69cb\u6587\uff09<\/h3>\n<pre class=\"lang:default decode:true\">class Stack[T]:\n    def __init__(self) -&gt; None:\n        self._items: list[T] = []\n\n    def push(self, item: T) -&gt; None:\n        self._items.append(item)\n\n    def pop(self) -&gt; T:\n        return self._items.pop()\n\nstack: Stack[int] = Stack()\nstack.push(1)\nvalue = stack.pop()  # value \u306f int<\/pre>\n<p>3.11 \u4ee5\u524d\u3067\u306f <code>typing.Generic<\/code> \u3092\u4f7f\u3063\u305f\u65e7\u69cb\u6587\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">from typing import Generic, TypeVar\n\nT = TypeVar(\"T\")\n\nclass Stack(Generic[T]):\n    def __init__(self) -&gt; None:\n        self._items: list[T] = []\n\n    def push(self, item: T) -&gt; None:\n        self._items.append(item)\n\n    def pop(self) -&gt; T:\n        return self._items.pop()<\/pre>\n<h2>\u78ba\u8a8d\u65b9\u6cd5<\/h2>\n<p>\u308f\u3056\u3068\u578b\u3092\u9593\u9055\u3048\u305f\u30b3\u30fc\u30c9\u3092\u7528\u610f\u3057\u3001\u8b66\u544a\u304c\u51fa\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\"># check.py\ndef add(a: int, b: int) -&gt; int:\n    return a + b\n\nresult: str = add(1, 2)  # int \u3092 str \u306b\u4ee3\u5165 \u2192 \u30a8\u30e9\u30fc\u306b\u306a\u308b\u306f\u305a<\/pre>\n<pre class=\"lang:default decode:true\">$ mypy check.py\ncheck.py:4: error: Incompatible types in assignment (expression has type \"int\", variable has type \"str\")  [assignment]\nFound 1 error in 1 file (checked 1 source file)<\/pre>\n<p>\u30a8\u30c7\u30a3\u30bf\uff08VS Code + Pylance \u306a\u3069\uff09\u3067\u3082\u540c\u3058\u7b87\u6240\u306b\u6ce2\u7dda\u304c\u8868\u793a\u3055\u308c\u307e\u3059\u3002<\/p>\n<h2>\u6ce8\u610f\u70b9<\/h2>\n<ul>\n<li>\u578b\u30d2\u30f3\u30c8\u306f\u5b9f\u884c\u6642\u306e\u578b\u5b89\u5168\u3092\u4fdd\u8a3c\u3057\u306a\u3044\u3002\u5b9f\u884c\u6642\u691c\u8a3c\u304c\u5fc5\u8981\u306a\u3089 <code>pydantic<\/code> \u306a\u3069\u3092\u4f75\u7528\u3057\u307e\u3059\u3002<\/li>\n<li><code>Any<\/code> \u306f\u578b\u30c1\u30a7\u30c3\u30af\u3092\u7121\u52b9\u5316\u3059\u308b\u578b\u3067\u3059\u3002\u4e71\u7528\u306f\u907f\u3051\u307e\u3059\u3002<\/li>\n<li>3.9 \u4ee5\u524d\u3067\u306f <code>typing.List<\/code> \/ <code>typing.Union<\/code> \u3092\u4f7f\u3046\u304b\u3001<code>from __future__ import annotations<\/code> \u3092\u4f75\u7528\u3057\u307e\u3059\u3002<\/li>\n<li>\u6bb5\u968e\u7684\u306b\u5c0e\u5165\u3067\u304d\u307e\u3059\u3002\u5909\u66f4\u983b\u5ea6\u304c\u9ad8\u3044\u30e2\u30b8\u30e5\u30fc\u30eb\u304b\u3089\u578b\u3092\u4ed8\u3051\u3066\u3044\u304f\u306e\u304c\u73fe\u5b9f\u7684\u3067\u3059\u3002<\/li>\n<\/ul>\n<h2>\u307e\u3068\u3081<\/h2>\n<ul>\n<li>\u578b\u30d2\u30f3\u30c8\u306f\u300c\u5b9f\u884c\u6642\u306b\u52b9\u304b\u306a\u3044\u30fb\u9759\u7684\u89e3\u6790\u3067\u52b9\u304f\u300d\u60c5\u5831\u3067\u3042\u308b\u3002<\/li>\n<li>\u57fa\u672c\u578b \u2192 <code>Optional<\/code>\/<code>Union<\/code> \u2192 \u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u578b \u2192 \u30b8\u30a7\u30cd\u30ea\u30af\u30b9\u306e\u9806\u3067\u7406\u89e3\u3059\u308b\u3068\u7121\u7406\u304c\u306a\u3044\u3002<\/li>\n<li><code>TypeVar<\/code> \u3068\u30b8\u30a7\u30cd\u30ea\u30c3\u30af\u30af\u30e9\u30b9\u3067\u3001\u6c4e\u7528\u7684\u306a\u30b3\u30fc\u30c9\u3082\u578b\u5b89\u5168\u306b\u66f8\u3051\u308b\u3002<\/li>\n<li>\u307e\u305a\u306f <code>mypy<\/code> \u3092\u5c0e\u5165\u3057\u3001\u5909\u66f4\u306e\u591a\u3044\u30e2\u30b8\u30e5\u30fc\u30eb\u304b\u3089\u6bb5\u968e\u7684\u306b\u578b\u3092\u4ed8\u3051\u3066\u3044\u304f\u306e\u304c\u304a\u3059\u3059\u3081\u3067\u3059\u3002<\/li>\n<\/ul>\n<p>\u578b\u30d2\u30f3\u30c8\u306f\u300c\u672a\u6765\u306e\u81ea\u5206\u3068\u540c\u50da\u3078\u306e\u8a2d\u8a08\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\u300d\u3067\u3082\u3042\u308a\u307e\u3059\u3002\u5c0f\u3055\u304f\u59cb\u3081\u3066\u3001\u30b3\u30fc\u30c9\u306e\u5b89\u5fc3\u611f\u3092\u80b2\u3066\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Python \u306f\u52d5\u7684\u578b\u4ed8\u3051\u8a00\u8a9e\u3067\u3059\u304c\u30013.5 \u4ee5\u964d\u3067\u5c0e\u5165\u3055\u308c\u305f\u300c\u578b\u30d2\u30f3\u30c8\uff08type hints\uff09\u300d\u3092\u4f7f\u3046\u3068\u3001\u95a2\u6570\u3084\u5909\u6570\u306b\u671f\u5f85\u3059\u308b\u578b\u3092\u6ce8\u91c8\u3068\u3057\u3066\u66f8\u3051\u307e\u3059\u3002\u578b\u30d2\u30f3\u30c8\u306f\u5b9f\u884c\u6642\u306b\u306f\u57fa\u672c\u7684\u306b\u7121\u8996\u3055\u308c\u307e\u3059\u304c\u3001mypy 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