Port suspicious markup builder and patchlevel.py so that they can be used with Python 2 and 3 without conversion.
diff --git a/Doc/tools/sphinxext/patchlevel.py b/Doc/tools/sphinxext/patchlevel.py
index 082858e..b070d60 100644
--- a/Doc/tools/sphinxext/patchlevel.py
+++ b/Doc/tools/sphinxext/patchlevel.py
@@ -68,4 +68,4 @@
         return version, release
 
 if __name__ == '__main__':
-    print get_header_version_info('.')[1]
+    print(get_header_version_info('.')[1])