message: Comment style nitpick for StrategyExtendV2.
diff: @@ -1164,8 +1164,8 @@ class StrategyExtendedV2(object):
  *Replica context vs. Cross-replica context*
  - _replica context_ is when we are in some function that is being called once
  - for each replica. Otherwise we are in cross-replica context, which is
  + A _replica context_ applies when we are in some function that is being called
  + once for each replica. Otherwise we are in cross-replica context, which is
  useful for calling `tf.distribute.Strategy` methods which operate across the
  replicas (like `reduce_to()`). By default you start in a replica context
  (the "default single replica context") and then some methods can switch you
  