fix on windows

Author: kumaraditya303

Objects/unicodeobject.c

@@ -1445,7 +1445,7 @@ unicode_convert_wchar_to_ucs4(const wchar_t *begin, const wchar_t *end,
 
     assert(unicode != NULL);
     assert(_PyUnicode_CHECK(unicode));
-    assert(_PyUnicode_KIND(unicode) == PyUnicode_4BYTE_KIND);
+    assert(PyUnicode_KIND(unicode) == PyUnicode_4BYTE_KIND);
     ucs4_out = PyUnicode_4BYTE_DATA(unicode);
 
     for (iter = begin; iter < end; ) {