Followup to a541bda2f5e2: Add a short comment.
diff --git a/Python/import.c b/Python/import.c
index 9773687..47839c5 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -1946,6 +1946,7 @@
 
             if (_Py_stat(filename, &statbuf) != 0 || S_ISDIR(statbuf.st_mode))
             {
+                /* it doesn't exist, or it's a directory */
                 Py_DECREF(filename);
                 continue;
             }