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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 get_user_id(self, attributes):
 """ For use when CAS_CREATE_USER_WITH_ID is True. Will raise ImproperlyConfigured exceptions when a user_id cannot be accessed. This is important because we shouldn't create Users with automatically assigned ids if we are trying to keep User primary key's in sync. """

        if not attributes:
            raise ImproperlyConfigured("CAS_CREATE_USER_WITH_ID is True, but "
                                       "no attributes were provided")

        user_id = attributes.get('id')

        if not user_id:
            raise ImproperlyConfigured("CAS_CREATE_USER_WITH_ID is True, but "
                                       "`'id'` is not part of attributes.")

        return user_id