@abc.abstractmethod
    def update_policy(self, context, policy):
Given a list of nodes to be executed (executionList), return the 
dataset/ETHPy150Open openstack/neutron/neutron/services/qos/notification_drivers/qos_base.py/QosServiceNotificationDriverBase.update_policy--crossover with--dataset/ETHPy150Open andrew-gardner/dependsworkflow/depends/depends_dag.py/DAG.groupIndicesInExecutionList