Fix off-by-one error in array size.
diff --git a/Modules/pyexpat.c b/Modules/pyexpat.c
index 011db63..cbe0a6e 100644
--- a/Modules/pyexpat.c
+++ b/Modules/pyexpat.c
@@ -779,7 +779,7 @@
     Make it as simple as possible.
 */
 
-static char template_buffer[256];
+static char template_buffer[257];
 PyObject * template_string=NULL;
 
 static void