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example/aitf-update-cache

@@ -116,6 +116,8 @@ def unlink_if_old(filename, expiration_time, stats):
     expiration time is epoch time, as returned by os.path.getmtime(path) 
     or time.time().
 
+    stats is a CleaningStats object (above)
+
     If the file doesn't exist, does nothing, does not raise an exception.
     This is on the theory that another process may have cleaned it up
     while we were considering doing so.