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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 remove_data_flow(self, data_flow_id, destroy=True):
 """ Removes a data flow from the container state :param int data_flow_id: the id of the data_flow to remove :raises exceptions.AttributeError: if the data_flow_id does not exist """

        if data_flow_id not in self._data_flows:
            raise AttributeError("The data_flow_id %s does not exist" % str(data_flow_id))

        self._data_flows[data_flow_id].parent = None
        return self._data_flows.pop(data_flow_id)