$ python3 fibonacci_doctest.py
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File "fibonacci_doctest.py", line 8, in __main__.fib
Failed example:
fib(0)
Expected:
0
Got:
1
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File "fibonacci_doctest.py", line 12, in __main__.fib
Failed example:
fib(10)
Expected:
55
Got:
89
…
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1 items had failures:
3 of 4 in __main__.fib
***Test Failed*** 3 failures.
We create an error in the previous example: We change
a, b = 0, 1
to
a, b = 1, 1