$ python fizzbuzz_test.py 
.F
======================================================================
FAIL: test_FizzBuzz_de2 (__main__.TestFizzBuzz)
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Traceback (most recent call last):
  File "fizzbuzz_test.py", line 12, in test_FizzBuzz_de2
    self.assertEqual(FizzBuzz(2), 2)
AssertionError: 1 != 2

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Ran 2 tests in 0.000s

FAILED (failures=1)