Method copy

Lib/collections/__init__.py:1099–1101

New ChainMap or subclass with a new copy of maps[0] and refs to maps[1:]

(self)

        return cls(dict.fromkeys(iterable, value))

    def copy(self):
        'New ChainMap or subclass with a new copy of maps[0] and refs to maps[1:]'
        return self.__class__(self.maps[0].copy(), *self.maps[1:])

    __copy__ = copy