i agree to you

then don't use it

That's the error message, the first value is what your function wrongly returned and the other one is the expected value, print the input to debug your code.

Agreed created the solution and then came across that the test cases aren't even working

Hi - first of all, I agree that the description/sense of the kata is a bit confusing.

But anyways, in description we have: ...no matter if it was in the past or it is in the future...

So the first example corresponds to +22 years in future, where father will be 58 years old, and son will be 29 years old, and indeed we have 58 = 2 * 29.

https://docs.codewars.com/languages/python#packages

sympy is not installed on Codewars.