Braces are required. (#280)

Closes #279

pep-0007.txt

@@ -91,8 +91,9 @@ Code lay-out
 
 * Code structure: one space between keywords like ``if``, ``for`` and
   the following left paren; no spaces inside the paren; braces are
-  strongly preferred but may be omitted where C permits, and they
-  should be formatted as shown::
+  required everywhere, even where C permits them to be omitted, but do
+  not add them to code you are not otherwise modifying.  All new C
+  code requires braces.  Braces should be formatted as shown::
 
       if (mro != NULL) {
           ...