def __missing__(self, key):
        if self.default_factory is None:
            raise KeyError(key)
        else:
            ret = self[key] = self.default_factory(name=key)
            return ret
def decode(value):
    if isinstance(value, bytes):
        value = value.decode(errors="surrogateescape")

    for char in ("\\", "\n", "\t"):
        value = value.replace(
            char.encode(encoding="unicode-escape").decode(), char
        )

    return value