def __copy__(self):
    cls = self.__class__
    copied_op = cls.__new__(cls)
    copied_op.obs = self.obs.copy()
    copied_op._eigvals_cache = self._eigvals_cache
    return copied_op
def __copy__(self):
    cls = self.__class__
    copied_op = cls.__new__(cls)
    copied_op.obs = self.obs.copy()
    copied_op._eigvals_cache = self._eigvals_cache
    return copied_op