def _get_hmacs(self, env, expires, scoped_keys, request_method=None):
        if not request_method:
            request_method = env['REQUEST_METHOD']
        return [
            (get_hmac(request_method, env['PATH_INFO'], expires, key), scope)
            for (key, scope) in scoped_keys]
Returns generator that indicates how many workers are RUNNING.
dataset/ETHPy150Open openstack/swift/swift/common/middleware/tempurl.py/TempURL._get_hmacs--crossover with--dataset/ETHPy150Open GoogleCloudPlatform/solutions-google-compute-engine-cluster-for-hadoop/gce_cluster.py/GceCluster._WorkerStatusChecker