diff --git a/Include/modsupport.h b/Include/modsupport.h
index a678257..54c7add 100644
--- a/Include/modsupport.h
+++ b/Include/modsupport.h
@@ -18,6 +18,10 @@
 extern DL_IMPORT(int) PyArg_VaParse(PyObject *, char *, va_list);
 extern DL_IMPORT(PyObject *) Py_VaBuildValue(char *, va_list);
 
+extern DL_IMPORT(int) PyModule_AddObject(PyObject *, char *, PyObject *);
+extern DL_IMPORT(int) PyModule_AddIntConstant(PyObject *, char *, long);
+extern DL_IMPORT(int) PyModule_AddStringConstant(PyObject *, char *, char *);
+
 #define PYTHON_API_VERSION 1009
 #define PYTHON_API_STRING "1009"
 /* The API version is maintained (independently from the Python version)