Question

I made a function that would ask a player to enter a letter until the letter was X, x, O or o.
But, whenever i call the function , somehow the while loop evaluates to False and never starts executing. What might be the problem ? Thank you very much.

def getLetter():
    letter = ""
    while letter not in "XxOo":
        print("Would you like to be X or O ?")
        letter = input()

Answer 1

The empty string is member of all strings. Just try it in the Python prompt:

>>> "" in "lol"
True

You can initialise letter to some thing you know is not among the choices, for example <not chosen yet>, instead of the empty string.