diff --git a/Doc/reference/lexical_analysis.rst b/Doc/reference/lexical_analysis.rst
index 5037da02726..ab1b7f52989 100644
--- a/Doc/reference/lexical_analysis.rst
+++ b/Doc/reference/lexical_analysis.rst
@@ -328,7 +328,9 @@ Keywords
 
 The following identifiers are used as reserved words, or *keywords* of the
 language, and cannot be used as ordinary identifiers.  They must be spelled
-exactly as written here::
+exactly as written here:
+
+.. sourcecode:: text
 
    False      class      finally    is         return
    None       continue   for        lambda     try