diff --git a/OpenSSL/py3k.h b/OpenSSL/py3k.h
index 2191526..2827f1f 100644
--- a/OpenSSL/py3k.h
+++ b/OpenSSL/py3k.h
@@ -19,6 +19,8 @@
 
 #define PyOpenSSL_MODRETURN(module) { return module; }
 
+#define FMT(name) ("y" name)
+
 #else /* (PY_VERSION_HEX >= 0x03000000) */
 
 #define PyOpenSSL_MODRETURN(module) { return; }
@@ -45,6 +47,8 @@
 void \
 init##name(void)
 
+#define FMT(name) ("s" name)
+
 #endif /* (PY_VERSION_HEX >= 0x03000000) */
 
 #endif /* PyOpenSSL_PY3K_H_ */