Mark PyUnicode_FromUCS[124] as private
diff --git a/Objects/stringlib/ucs4lib.h b/Objects/stringlib/ucs4lib.h
index 776d65f..be1206a 100644
--- a/Objects/stringlib/ucs4lib.h
+++ b/Objects/stringlib/ucs4lib.h
@@ -19,7 +19,7 @@
 #define STRINGLIB_FILL           Py_UNICODE_FILL
 #define STRINGLIB_STR            PyUnicode_1BYTE_DATA
 #define STRINGLIB_LEN            PyUnicode_GET_LENGTH
-#define STRINGLIB_NEW            PyUnicode_FromUCS4
+#define STRINGLIB_NEW            _PyUnicode_FromUCS4
 #define STRINGLIB_RESIZE         not_supported
 #define STRINGLIB_CHECK          PyUnicode_Check
 #define STRINGLIB_CHECK_EXACT    PyUnicode_CheckExact