F......F......E.

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

ERROR: testSum (tester.ProblemTests)

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

Traceback (most recent call last):

  File ".../test.py", line 103, in testSum

    self.assertEqual(Interval(6, None), Interval(6, 18) + Interval(18, None))

  File ".../fn43539/2007-04-04 13:22:27/user.py", line 144, in __add__

    raise ValueError("Result is not an interval")

ValueError: Result is not an interval



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

FAIL: testCmp (tester.ProblemTests)

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

Traceback (most recent call last):

  File ".../test.py", line 110, in testCmp

    self.assertTrue(Interval(7, 22) > Interval(8, 22))

AssertionError



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

FAIL: testIntersects (tester.ProblemTests)

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

Traceback (most recent call last):

  File ".../test.py", line 73, in testIntersects

    self.assertTrue(Interval(2, 3).intersects(Interval(3, 4)))

AssertionError



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

Ran 16 tests in 0.010s



FAILED (failures=2, errors=1)