Validation checking

[ichabod801]

Don't test where invalid == True, just test where invalid:.

When you return three values using tuple syntax, you need to assign three values using tuple syntax. Take this function:

def foo():
    return True, 801, 'a duck'

If I do invalid = foo(), then invalid is equal to (True, 801, 'a duck'). What should be done is invalid, number, floats = foo(). Then invalid is True, number is 801, and floats is 'a duck'.

@ perfringo: I think by four in a row he means something like Connect Four. You drop pieces into slots and they stack on top of each other. You try to get four pieces in a row, orthogonally or diagonally.