Friends Ages

import Ask

#Declare Variables
oldestFriend = 0
middleFriend = 0
youngestFriend = 0

#Function to sort ages (in ascending order)
def sortFriends(Friend):
    #Reference variables outside function
    global youngestFriend
    global middleFriend
    global oldestFriend

    #if new friend is older than middle/inital friend
    if (Friend > middleFriend) and (oldestFriend == 0):
        oldestFriend = Friend

    #if new friend is the same age or younger than middle/inital friend
    elif (Friend <= middleFriend) and (youngestFriend == 0):
        youngestFriend = Friend

    #if new friend is even older than the two previously entered friends
    elif (Friend > oldestFriend) and (oldestFriend != 0):
        youngestFriend = middleFriend
        middleFriend = oldestFriend
        oldestFriend = Friend

    #if new friend is even younger than the two previously entered friends
    elif (Friend <= youngestFriend) and (youngestFriend != 0):
        oldestFriend = middleFriend
        middleFriend = youngestFriend
        youngestFriend = Friend

    #if new friend is in between the two previously entered friends and older than middle
    elif (Friend > middleFriend) and (Friend < oldestFriend) and (oldestFriend !=0):
        youngestFriend = middleFriend
        middleFriend = Friend

    #if new friend is in between the two previously entered friends and younger than middle
    elif (Friend < middleFriend) and (Friend > youngestFriend) and (youngestFriend !=0):
        oldestFriend = middleFriend
        middleFriend = Friend

#Start with first friend in the middle
middleFriend = Ask.forInt("What's the age of one of your friends?")

#and compare following friends with inital friend
sortFriends(Ask.forInt("What's the age of another one of your friends?"))
sortFriends(Ask.forInt("What's the age of a third friend of yours?"))

equalAgeGap = False

if (middleFriend - youngestFriend) == (oldestFriend - middleFriend):
    equalAgeGap = True

if equalAgeGap:
    print("The ages of your friends are {0} years apart.".format(middleFriend - youngestFriend))
else:
    print("Your friends ages are not the same.")