..........E.....

======================================================================

ERROR: testLen (tester.ProblemTests)

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Traceback (most recent call last):

  File ".../test.py", line 97, in testLen

    self.assertEqual(0, len(Interval(-22, None)))

  File ".../fn30881/2007-04-02 00:13:22/user.py", line 99, in __len__

    return O

NameError: global name 'O' is not defined



----------------------------------------------------------------------

Ran 16 tests in 0.006s



FAILED (errors=1)