Automate the boring stuff with Python: Comma Code

Question

Currently working my way through this beginners book and have completed one of the practice projects \'Comma Code\' which asks the user to construct a program which:

Answer 1

def commacode(mylist):
    mylist[-1] = 'and ' + mylist[-1]
    mystring = ', '.join(mylist)
    return mystring

spam = ['apple', 'bananas', 'tofu', 'cats']

print commacode(spam)