Issue #19902: Added list of logging levels.
diff --git a/Doc/library/logging.rst b/Doc/library/logging.rst
index 68e359e..e8189c2 100644
--- a/Doc/library/logging.rst
+++ b/Doc/library/logging.rst
@@ -114,6 +114,8 @@
If the root is reached, and it has a level of NOTSET, then all messages will be
processed. Otherwise, the root's level will be used as the effective level.
+ See :ref:`levels` for a list of levels.
+
.. method:: Logger.isEnabledFor(lvl)
@@ -281,6 +283,35 @@
.. versionchanged:: 2.5
*func* and *extra* were added.
+
+.. _levels:
+
+Logging Levels
+--------------
+
+The numeric values of logging levels are given in the following table. These are
+primarily of interest if you want to define your own levels, and need them to
+have specific values relative to the predefined levels. If you define a level
+with the same numeric value, it overwrites the predefined value; the predefined
+name is lost.
+
++--------------+---------------+
+| Level | Numeric value |
++==============+===============+
+| ``CRITICAL`` | 50 |
++--------------+---------------+
+| ``ERROR`` | 40 |
++--------------+---------------+
+| ``WARNING`` | 30 |
++--------------+---------------+
+| ``INFO`` | 20 |
++--------------+---------------+
+| ``DEBUG`` | 10 |
++--------------+---------------+
+| ``NOTSET`` | 0 |
++--------------+---------------+
+
+
.. _handler:
Handler Objects
@@ -321,6 +352,7 @@
severe than *lvl* will be ignored. When a handler is created, the level is set
to :const:`NOTSET` (which causes all messages to be processed).
+ See :ref:`levels` for a list of levels.
.. method:: Handler.setFormatter(form)