E....

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

ERROR: test_empties (tester.ProblemTests)

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Traceback (most recent call last):

  File ".../test.py", line 39, in test_empties

    self.assertNoOrder([], tags_by_band('My Jolly Band'))

  File ".../fn43813/2008-03-26 16:17:46/user.py", line 3, in tagsByBand

    result = reduce(lambda tags1, tags2: tags1 + tags2, [[]+list(song[-1]) for song in songs if song[1] == band_name], list(filter(lambda band: band[0] == band_name, bands)[0][1]));

IndexError: list index out of range



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Ran 5 tests in 0.001s



FAILED (errors=1)