diff --git a/doc/calc.py b/doc/calc.py
old mode 100644
new mode 100755
index b222218..4b7890b
--- a/doc/calc.py
+++ b/doc/calc.py
@@ -107,7 +107,7 @@ def on_exp(self, target, option, names, values):
     #include <string.h>
     #include "Python.h"
     #define YYSTYPE void *
-    #include "tokens.h"
+    #include "tmp.tab.h"
     extern void *py_parser;
     extern void (*py_input)(PyObject *parser, char *buf, int *result,
                             int max_size);