diff --git a/Objects/codeobject.c b/Objects/codeobject.c
index cb8f3e4..01a637a 100644
--- a/Objects/codeobject.c
+++ b/Objects/codeobject.c
@@ -296,7 +296,7 @@
 	if (co->co_firstlineno != 0)
 		lineno = co->co_firstlineno;
 	if (co->co_filename && PyUnicode_Check(co->co_filename))
-		filename = PyUnicode_AsString(co->co_filename);
+		filename = _PyUnicode_AsString(co->co_filename);
 	return PyUnicode_FromFormat(
 	                "<code object %.100U at %p, file \"%.300s\", line %d>",
 	                co->co_name, co, filename, lineno);