This has already been raised as an issue, but in Python some methods time out. The test cases should be made smaller.

edit

OK, I've fixed this issue, the output isn't printed any more.

I'm not sure what you are saying tbh. If you're trying to say that a wrong solution will pass the tests, I think that's quite unlikely, as there are many tests, and a test with a large array.
Remember that the rounding is taken after calculation of the average, and that it has to match exactly with the expected average, to 2 d.p.

Note that this method would fail for certain arrays, for example an array of ones of length 200.