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Your function fails on reverse(“Python!”). It returns “!nohtyP “ when it should return “!nohtyP”.
what kind of error is this?
Not an error, but I presume the Codecademy environment telling you that one of the test cases it’s using to validate that your solution is correct are failing.
Note that "!nohtyP " and "!nohtyP" are not the same thing. Hopefully why these are different things should be self evident.