Issue #25161: Add full stops in documentation; patch by Takase Arihiro
diff --git a/Doc/library/exceptions.rst b/Doc/library/exceptions.rst
index 9291c18..fe14656 100644
--- a/Doc/library/exceptions.rst
+++ b/Doc/library/exceptions.rst
@@ -496,7 +496,7 @@
 
 .. exception:: SyntaxWarning
 
-   Base class for warnings about dubious syntax
+   Base class for warnings about dubious syntax.
 
 
 .. exception:: RuntimeWarning