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

I am a fairly new pythonista. In the question it was asked that the function return the list contents as a string in the format that the other solutions in this forum have 'printed' it. Following is (in my opinion) a cleaner solution to this problem.

This illustrates the comma code solution of chapter 4 [Lists] in Automate The Boring Stuff.

def comma_code(argument):

    argument_in_string = ''
    argument_len = len(argument)
    for i in range(argument_len):
        if i == (argument_len - 1):
            argument_in_string = argument_in_string + 'and ' + argument[i]
            return argument_in_string

        argument_in_string = argument_in_string + argument[i] + ', '

spam = ['apples', 'bananas', 'tofu', 'cats']
return_value = comma_code(spam)
print(return_value)"