DCP51 - Shuffling a deck of cards

'''
This problem was asked by Facebook.
Given a function that generates perfectly random numbers between 1 and k (inclusive), where k is an input, write a function
that shuffles a deck of cards represented as an array using only swaps.
It should run in O(N) time.
Hint: Make sure each one of the 52! permutations of the deck is equally likely.
'''
from random import randrange, shuffle

# 1st Function
def generateDeckOfCards():
    ace = "A"
    numbers = list()
    figures = "JQK"
    categories = ["heart", "spade", "diamond", "club"]
    for i in range(2, 11):
        numbers.append(str(i))
    values = list()
    # Generate all the 13 values
    values.append(ace)
    for number in numbers:
        values.append(number)
    for figure in figures:
        values.append(figure)
    # Now, I will generate all the cards (4 categories * 13 values)
    cards = list()
    for category in categories:
        for value in values:
            cards.append(str(value) + "-" + str(category))
    return cards


# 2nd Function
def random(k):
    if k > 52 * 51 / 2 / 2:
        return -1000
    # Here my swaps will be <= all the comparisons between my elements
    return randrange(1, k+1)

# 3rd Function
def doISwap():
    flag = randrange(0, 2)
    if flag == 0:
        return False
    return True

# 4th Function
def shuffleCards(cards, k):
    cards = generateDeckOfCards()
    K = random(k)
    # I will first shuffle cards with the given method and then I will begin the process with my extra
    shuffled = cards.copy()
    shuffle(shuffled)
    # print(shuffled)
    # Now, the variable "shuffled" contains a randomly shuffled version of "cards" list
    SUM = 0
    for i in range(len(shuffled)-1):
        for j in range(i, len(shuffled)):
            swap = doISwap()
            if SUM == K:
                break
            if swap == True:
                SUM += 1
                shuffled[i], shuffled[j] = shuffled[j], shuffled[i]
    return shuffled


# MAIN FUNCTION
cards = generateDeckOfCards()
shuffled = shuffleCards(cards, 10)
print(shuffled)