Random Mutation of Data

#This program will take two words of equal lengths and see how many
#attempts it takes to change the first into the second by randomly
#changing one letter at a time.

import random

#define variables
word1 = ""
word2 = ""
array1 = ""
array2 = ""
rand_pos = 0
rand_let = 0
count = 0


#ask for two words and validate that they are equal lengths and different words
print("Welcome to the Random Mutation Simulator!")
print("Give me two different words of equal lengths,")
print("and I will tell you how many times it takes")
print("to change the first into the second by randomly")
print("changing one letter at a time.")
word1 = input("What would you like your first word to be?  ")
word2 = input("What would you like your second word to be?  ")
while ((word1 == word2) or (len(word1) != len(word2))):
    if (word1 == word2):
        print("Those are the same word!")
        word2 = input("Please choose a different second word. Your first word was: " + word1 + "  ")
    else: # if (len(word1) != len(word2))
        print("Those words are different lengths!")
        word2 = input("Please choose a second word of the same length. Your first word was: " + word1 + "  ")

word1 = word1.upper()
word2 = word2.upper()

print("Please wait while I try to turn " + word1 + " into " + word2 + ".....")

#change the word strings into arrays for manipulation
array1 = list(word1)
array2 = list(word2)


#simulation loop
while (array1 != array2):

    #generate a random position in the array
    rand_pos = random.randrange(len(word1))

    #generate a random number from 1-26 and use that to get a random letter
    #assign the random letter to the random position in the array
    rand_let = (random.randrange(26)+1)
    if (rand_let == 1):
        array1[rand_pos] = "A"
    elif (rand_let == 2):
        array1[rand_pos] = "B"
    elif (rand_let == 3):
        array1[rand_pos] = "C"
    elif (rand_let == 4):
        array1[rand_pos] = "D"
    elif (rand_let == 5):
        array1[rand_pos] = "E"
    elif (rand_let == 6):
        array1[rand_pos] = "F"
    elif (rand_let == 7):
        array1[rand_pos] = "G"
    elif (rand_let == 8):
        array1[rand_pos] = "H"
    elif (rand_let == 9):
        array1[rand_pos] = "I"
    elif (rand_let == 10):
        array1[rand_pos] = "J"
    elif (rand_let == 11):
        array1[rand_pos] = "K"
    elif (rand_let == 12):
        array1[rand_pos] = "L"
    elif (rand_let == 13):
        array1[rand_pos] = "M"
    elif (rand_let == 14):
        array1[rand_pos] = "N"
    elif (rand_let == 15):
        array1[rand_pos] = "O"
    elif (rand_let == 16):
        array1[rand_pos] = "P"
    elif (rand_let == 17):
        array1[rand_pos] = "Q"
    elif (rand_let == 18):
        array1[rand_pos] = "R"
    elif (rand_let == 19):
        array1[rand_pos] = "S"
    elif (rand_let == 20):
        array1[rand_pos] = "T"
    elif (rand_let == 21):
        array1[rand_pos] = "U"
    elif (rand_let == 22):
        array1[rand_pos] = "V"
    elif (rand_let == 23):
        array1[rand_pos] = "W"
    elif (rand_let == 24):
        array1[rand_pos] = "X"
    elif (rand_let == 25):
        array1[rand_pos] = "Y"
    elif (rand_let == 26):
        array1[rand_pos] = "Z"

    #Count how many loops it takes to make the arrays match
    count = count + 1

#once the arrays match, tell the user how many attempts it took
print("It took me " + str(count) + " tries to turn " + word1 + " into " + word2 + ".")