def _get_run_by_other_worker(worker):
 task_sets = _get_external_workers(worker).values()
 return functools.reduce((lambda a, b: (a | b)), task_sets, set())

def _get_run_by_other_worker ( worker ) : task_sets = _get_external_workers ( worker ) . values ( ) return functools . reduce ( ( lambda a , b : ( a | b ) ) , task_sets , set ( ) )
this returns a set of the tasks that are being run by other worker .