#759525: document that dir() doesn't return metaclass attrs when given a class as arg.

Doc/library/functions.rst

@@ -302,7 +302,8 @@ available.  They are listed here in alphabetical order.
       Because :func:`dir` is supplied primarily as a convenience for use at an
       interactive prompt, it tries to supply an interesting set of names more than it
       tries to supply a rigorously or consistently defined set of names, and its
-      detailed behavior may change across releases.
+      detailed behavior may change across releases.  For example, metaclass attributes
+      are not in the result list when the argument is a class.
 
 
 .. function:: divmod(a, b)

Doc/library/inspect.rst

@@ -195,6 +195,11 @@ Note:
    name.  If the optional *predicate* argument is supplied, only members for which
    the predicate returns a true value are included.
 
+   .. note::
+
+      :func:`getmembers` does not return metaclass attributes when the argument
+      is a class (this behavior is inherited from the :func:`dir` function).
+
 
 .. function:: getmoduleinfo(path)