How to pass value from method to function

[iFunKtion]

So the problem I am having, and now i have followed what everyone is saying, is that it is passing None to the function, so after testing, I get on all but the empty list test in my test suite

Unbound error variable 'first' referenced before assignment 

Which implies to me that it is completely missing tie if statements which I don't understand. when i run my original code, it does what I expect, yet take it out of the function and pass it to the function, and it all falls apart.

Have I not converted everything to python3 correctly?

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Ah, I have a break through, thank you all for your help, I changed the range x was working on to 0, and another test was passed, it now only fails on an empty list and single item list which is what I was expecting it to do, as I had not written the code to deal with that yet. Thank you very much for your help. I think I nearly get it now.