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

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

ERROR: testExpand (tester.ProblemTests)

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Traceback (most recent call last):

  File ".../test.py", line 62, in testExpand

    self.assertEqual(Interval(-3, 10), i.expand(right=-1))

TypeError: expand() got an unexpected keyword argument 'right'



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Ran 16 tests in 0.006s



FAILED (errors=1)