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

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

ERROR: testLen (tester.ProblemTests)

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Traceback (most recent call last):

  File ".../test.py", line 95, in testLen

    self.assertEqual(5, len(Interval(0, 5)))

  File ".../fn31072/2007-04-02 13:55:51/user.py", line 121, in __len__

    return ceil(self.vright-self.vleft)

NameError: global name 'ceil' is not defined



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Ran 16 tests in 0.007s



FAILED (errors=1)