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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_data_flow_m(self, data_flow_id):
 """Searches and return the data flow model with the given in the given container state model :param data_flow_id: The data flow id to be searched :return: The model of the data flow or None if it is not found """

        for data_flow_m in self.data_flows:
            if data_flow_m.data_flow.data_flow_id == data_flow_id:
                return data_flow_m
        return None