Oh, I didn't even realize it thought my comments were cheating...
I just assumed it was a cryptic message I wasn't understanding.

There seems to be something wrong with cheating detection.
I'm basically just stringing two of my old solutions to different problems, and I get the error message

No cheating!
You can't use .com, .com: ['.com', '.com'] should equal []

No, actually, the other two are wrong.

But it still wouldn't work, as this code only allows nesting of different braces.

Mentioning the wanted precision in the problem description would be nice.

Or, even better, having tests that check if the answer is close enough, rather than expecting absolute precision in calculations with floats.

Because (int or float) will always be true.

You probably wanted isinstance(r, (int, float)), although typechecking is rarely the correct solution in Python.