def request_cpus(self, name, url):
        "return a list of hosts for this coordinator to run processors on"
        try:
            c = self.coordinators[url]
        except __HOLE__:
            print >>sys.stderr, 'request_cpus: unknown coordinator %s @ %s' \
                    % (name, url)
            return [] # HAND BACK AN EMPTY LIST
        # Calculate how many CPUs each coordinator should get.
        self.assign_load()
        # Assign free CPUs to coordinators which need them.
        self.assign_processors()
        new_cpus=tuple(c.new_cpus) # MAKE A NEW COPY OF THE LIST OF HOSTS
        del c.new_cpus[:] # EMPTY OUR LIST
        return new_cpus
dataset/ETHPy150Open cjlee112/pygr/pygr/coordinator.py/ResourceController.request_cpus