新しいインスタンスを生成可能なクラス。MixInとして使っても良い。

reconstructable.py

import copy
from typing import Any, Self


class Reconstructable:
    _init_args: tuple[Any, ...]
    _init_kwds: dict[str, Any]

    @classmethod
    def reconstructable_init(cls, *args: Any, **kwds: Any) -> Self:
        instance = cls(*copy.deepcopy(args), **copy.deepcopy(kwds))
        instance._init_args = args
        instance._init_kwds = kwds
        return instance

    @property
    def is_reconstructable(self) -> bool:
        return hasattr(self, "_init_args") and hasattr(self, "_init_kwds")

    def new(self) -> Self:
        if self.is_reconstructable:
            return self.__class__.reconstructable_init(*self._init_args, **self._init_kwds)
        else:
            raise RuntimeError(
                "Can not create new instance! Did you forget to use `reconstructable_init`"
                "instead of `__init___` when creating a instance?"
            )