Python 2 compatibility. (#5887)

python/ray/autoscaler/autoscaler.py

@@ -354,7 +354,7 @@ class NodeLauncher(threading.Thread):
         logger.info(prefix + " {}".format(statement))
 
 
-class ConcurrentCounter():
+class ConcurrentCounter(object):
     def __init__(self):
         self._value = 0
         self._lock = threading.Lock()

python/ray/autoscaler/log_timer.py

@@ -8,7 +8,7 @@ import logging
 logger = logging.getLogger(__name__)
 
 
-class LogTimer():
+class LogTimer(object):
     def __init__(self, message):
         self._message = message