diff --git a/src/proto/if_python.pro b/src/proto/if_python.pro
index 793b6ee..ec12402 100644
--- a/src/proto/if_python.pro
+++ b/src/proto/if_python.pro
@@ -1,6 +1,7 @@
 /* if_python.c */
 int python_enabled __ARGS((int verbose));
 void python_end __ARGS((void));
+int python_loaded __ARGS((void));
 void ex_python __ARGS((exarg_T *eap));
 void ex_pyfile __ARGS((exarg_T *eap));
 void python_buffer_free __ARGS((buf_T *buf));