There are now sixteen isfoo functions.

Doc/library/inspect.rst

@@ -28,7 +28,7 @@ Types and members
 -----------------
 
 The :func:`getmembers` function retrieves the members of an object such as a
-class or module. The fifteen functions whose names begin with "is" are mainly
+class or module. The sixteen functions whose names begin with "is" are mainly
 provided as convenient choices for the second argument to :func:`getmembers`.
 They also help you determine when you can expect to find the following special
 attributes: