total=TrueのTypedDictで必須でないキーを表す
By default, all keys must be present in a TypedDict. It is possible to mark individual keys as non-required using NotRequired:
https://docs.python.org/ja/3/library/typing.html#typing.TypedDict
「デフォルトではすべてのキーがrequired」（total=True）
code:ドキュメントの例.py
class Point2D(TypedDict):
x: int
y: int
label: NotRequiredstr
NotRequiredはPython 3.11から可能
https://docs.python.org/ja/3/library/typing.html#typing.NotRequired
PEP 655 – Marking individual TypedDict items as required or potentially-missing
3.10以前はtyping-extensionsで