did I just write the single best one liner in a kata?? cant believe myself

There's no issue with the Python version. Something in your solution must be causing it.

In python I am getting a SyntaxError:
File "main.py", line 3
test.assert_equals(openOrSenior(return),['Open', 'Senior', 'Open', 'Senior'])
^
SyntaxError: invalid syntax
Code works when I run it somewhere else.

I lack a better term to refer to the hard coded checks in this answer before just doing the logical stuff.

There is no memoization (if thats what you mean)

Does this form of memotisation reduce process time for this situation at any amount?

I'm actually kind of scared it might xD