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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 find_page_of_state_m(self, state_m):
 """Return the identifier and page of a given state model :param state_m: The state model to be searched :return: page containing the state and the state_identifier """

        for state_identifier, page_info in list(self.tabs.items()):
            if page_info['state_m'] is state_m:
                return page_info['page'], state_identifier
        return None, None