Issue #8162: logging: Clarified docstring and documentation for disable function.

Doc/library/logging.rst

@@ -735,7 +735,11 @@ functions.
 
    Provides an overriding level *lvl* for all loggers which takes precedence over
    the logger's own level. When the need arises to temporarily throttle logging
-   output down across the whole application, this function can be useful.
+   output down across the whole application, this function can be useful. Its
+   effect is to disable all logging calls of severity *lvl* and below, so that
+   if you call it with a value of INFO, then all INFO and DEBUG events would be
+   discarded, whereas those of severity WARNING and above would be processed
+   according to the logger's effective level.
 
 
 .. function:: addLevelName(lvl, levelName)

Lib/logging/__init__.py

@@ -1557,7 +1557,7 @@ def log(level, msg, *args, **kwargs):
 
 def disable(level):
     """
-    Disable all logging calls less severe than 'level'.
+    Disable all logging calls of severity 'level' and below.
     """
     root.manager.disable = level