missed async_

Author: crwilcox

google/datalab/utils/_async.py

@@ -23,7 +23,7 @@
 from future.utils import with_metaclass
 
 
-class _async(with_metaclass(abc.ABCMeta, object)):
+class async_(with_metaclass(abc.ABCMeta, object)):
   """ Base class for async_function/async_method. Creates a wrapped function/method that will
       run the original function/method on a thread pool worker thread and return a Job instance
       for monitoring the status of the thread.