#12389: fix missing space at sentence end.
diff --git a/Doc/library/urllib.rst b/Doc/library/urllib.rst
index 7f97673..503760b 100644
--- a/Doc/library/urllib.rst
+++ b/Doc/library/urllib.rst
@@ -210,7 +210,7 @@
Replace special characters in *string* using the ``%xx`` escape. Letters,
digits, and the characters ``'_.-'`` are never quoted. By default, this
- function is intended for quoting the path section of the URL.The optional
+ function is intended for quoting the path section of the URL. The optional
*safe* parameter specifies additional characters that should not be quoted
--- its default value is ``'/'``.