def _make_lock_uri(cloud_tmp_dir, cluster_id, step_num):
 return ((((cloud_tmp_dir + 'locks/') + cluster_id) + '/') + str(step_num))

def _make_lock_uri ( cloud_tmp_dir , cluster_id , step_num ) : return ( ( ( ( cloud_tmp_dir + 'locks/' ) + cluster_id ) + '/' ) + str ( step_num ) )
generate the uri to lock the cluster cluster_id .