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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 _UpdateSessionIfRequired(self, request_headers, response_result, response_headers):
 """ Updates session if necessary. :param dict response_result: :param dict response_headers: :param dict response_headers :return: None, but updates the client session if necessary. """


        '''if this request was made with consistency level as session, then update
        the session'''

        if response_result is None or response_headers is None:
            return

        is_session_consistency = False
        if http_constants.HttpHeaders.ConsistencyLevel in request_headers:
            if documents.ConsistencyLevel.Session == request_headers[http_constants.HttpHeaders.ConsistencyLevel]:
                is_session_consistency = True
              
        if is_session_consistency:
            # update session
            self.session.update_session(response_result, response_headers)