beginner question (True False help)

[eschneider92 at comcast.net]

This is what I ended up with btw. Does this insult anyone's more well-attuned Pythonic sensibilities? 

letters='abcdefghijkl' 
def repeat(): 
    print('wanna go again?') 
    batman=input() 
    if batman in ('y','yes'): 
        main() 
    else: 
        return 
def main(): 
    print('guess a letter') 
    batman=input() 
    if batman in letters: 
        print('ok that letter was in letters') 
        repeat() 
    else: 
        print('asdasdasd') 
        repeat() 
main() 
print('how ya doin')