Another class

def comparePeople(a, b):

    return cmp(a.name, b.name)



class Person():

    def __init__(self, name):

        self.name = name

        self.friends = []



    def addFriend(self, other):

        self.friends.append(other)

        other.friends.append(self)



    def getFriends(self):

        return sorted(self.friends, comparePeople)



def run():

    people = {}

    while True:

        cmd = raw_input('Command? ')

        parts = cmd.split()

        if parts[0] == 'add':

            a = Person(parts[1])

            people[a.name] = a

        elif parts[0] == 'friend':

            a = people[parts[1]]

            b = people[parts[2]]

            a.addFriend(b)

        elif parts[0] == 'friends':

            a = people[parts[1]]

            for b in a.getFriends():

                print b.name

        elif parts[0] == 'quit':

            return

        else:

            print 'unknown command', parts[0]



run()