--- a/tests/test-context.py	Thu May 05 16:20:53 2016 +0200
+++ b/tests/test-context.py	Wed Apr 20 19:53:01 2016 +0000
@@ -14,7 +14,7 @@
 
 # create 'foo' with fixed time stamp
 f = open('foo', 'wb')
-f.write('foo\n')
+f.write(b'foo\n')
 f.close()
 os.utime('foo', (1000, 1000))