--- a/tests/filterpyflakes.py	Tue Aug 11 13:48:57 2015 +0800
+++ b/tests/filterpyflakes.py	Thu Aug 13 22:10:52 2015 +0900
@@ -2,7 +2,7 @@
 
 # Filter output by pyflakes to control which warnings we check
 
-import sys, re, os
+import sys, re
 
 def makekey(typeandline):
     """
@@ -42,7 +42,7 @@
     else:
         continue # no pattern matched, next line
     fn = line.split(':', 1)[0]
-    f = open(os.path.join(os.path.dirname(os.path.dirname(__file__)), fn))
+    f = open(fn)
     data = f.read()
     f.close()
     if 'no-' 'check-code' in data: