Int Object is not callable

[deanhystad]

length()? Where is the length() function defined?

Why are you complicating things by doing this:

Output:
Do you want uppercase letters? 
[a] yes 
[b] no 

Instead of

Do you want uppercase letters (y/n)?

Adding [a] and [b] makes the prompt longer, adds confusion to what you should enter ('yes' or 'a'?) and adds extra code to handle the unnecessary confusion.