Small grammatical fix; missing comma.
diff --git a/Doc/ext/ext.tex b/Doc/ext/ext.tex
index 93f8232..1ae0421 100644
--- a/Doc/ext/ext.tex
+++ b/Doc/ext/ext.tex
@@ -244,7 +244,7 @@
The choice of which exception to raise is entirely yours. There are
predeclared C objects corresponding to all built-in Python exceptions,
-e.g. \cdata{PyExc_ZeroDivisionError} which you can use directly. Of
+e.g.\ \cdata{PyExc_ZeroDivisionError}, which you can use directly. Of
course, you should choose exceptions wisely --- don't use
\cdata{PyExc_TypeError} to mean that a file couldn't be opened (that
should probably be \cdata{PyExc_IOError}). If something's wrong with