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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def change_state(self, key, value):
 """ Changes the state of the instance data with the given ``key`` and the provided ``value``. Wrapping with a decorator is probably not necessary. :param key: A ``str`` containing the key to update :param value: A value to change the ``key`` to :return: None """

        if key not in VALID_KEYS:
            raise InvalidState
        self._data[key] = value