Given a list of people, pick secret santa for everyone. People form the same family shouldn't be santas for each other.

secret_santa.py

def parse(people):
    """ 
    returns a list of tuples; first element in tuple - last name; second element - a dict 
    """
    people_dicts = [dict(zip(("first", "last", "email"), person.split())) for person in people.splitlines()]
    return [(d["last"], d) for d in people_dicts]
    
def santafy(l):
    
    def index(i):
        return i % len(l)
    
    def swap(x, y):
        l[x], l[y] = l[y], l[x]
    
    for x in range(len(l)):
        if l[index(x)][0] == l[index(x + 1)][0]:
            for xx in range(len(l)):
                if l[index(x + 1 + xx)][0] != l[index(x + 1 + xx + 1)][0]:
                    swap(index(x + 1 + xx), index(x + 1 + xx + 1))
                    return santafy(l)
    
    return l
    
def report(l):
    def index(i):
        return i % len(l)
    
    for x in range(len(l)):
        print "{0} is Santa for {1} {2}".format(l[index(x)][1]["email"], l[index(x+1)][1]["first"], l[index(x+1)][1]["last"])
    
    
report(santafy(parse("""Luke Skywalker <luke@theforce.net>
Leia Skywalker <leia@therebellion.org>
Harry Potter <harry@hogwarts.com>
Lily Potter <lily@magic.org>
Bruce Wayne <bruce@imbatman.com>
Sarah Connor <sarah@terminator.com>
John Connor <john@skynet.com>""")))