$ python3 fibonacci_unittest.py
F
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FAIL: testCalculation (__main__.FibonacciTest)
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Traceback (most recent call last):
File "fibonacci_unittest.py", line 7, in testCalculation
self.assertEqual(fib(0), 0)
AssertionError: 1 != 0
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Ran 1 test in 0.000s
FAILED (failures=1)