def register_client(self, client_id):
        self.clients[client_id] = True
Creates a query object that will inject changes into results.
dataset/ETHPy150Open RobotWebTools/rosbridge_suite/rosbridge_library/src/rosbridge_library/internal/publishers.py/MultiPublisher.register_client--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/datastore/datastore_query.py/inject_results