Why does 'nothing' count as a string?

[snippsat]

So… my question is, why does python think that nothing or a zero length string IS in ‘abcdefg’?

A empty string is a substring of every string.

>>> '' in 'hello'
True
>>> '' in 'h'
True
>>> '' in ''
True

The easiest solution for your code is to add list('abcdefg') then do not need to test for empty string.

>>> 'h' in list('hello')
True
>>> '' in list('hello')
False