Improve highlighting of some code blocks. (GH-6401)

(cherry picked from commit 46936d5a71d1683dbd8ddb6d7f39aab50ecfec50)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
diff --git a/Doc/library/tokenize.rst b/Doc/library/tokenize.rst
index 02a0428..4c0a0ce 100644
--- a/Doc/library/tokenize.rst
+++ b/Doc/library/tokenize.rst
@@ -218,7 +218,7 @@
 of the line/column coordinates where the token is found, the second column is
 the name of the token, and the final column is the value of the token (if any)
 
-.. code-block:: sh
+.. code-block:: shell-session
 
     $ python -m tokenize hello.py
     0,0-0,0:            ENCODING       'utf-8'
@@ -244,7 +244,7 @@
 
 The exact token type names can be displayed using the :option:`-e` option:
 
-.. code-block:: sh
+.. code-block:: shell-session
 
     $ python -m tokenize -e hello.py
     0,0-0,0:            ENCODING       'utf-8'