Encryptor

"""ENCRYPTOR TEST"""
def key():
    a = True
    inp = int(raw_input("please enter a key: "))
    if inp <= 35:
        return inp
    else:
        while a == True:
            inp = int(raw_input("please enter a key: "))
            if inp <= 35:
                    a = False
    return inp

def encrypt(eord):
    output = ""
    alphabet = ["7","a","0","b","c","5","d","e","6","f","g","1","h","i","j","k","8","l","3","m","n","2","o","p","q","9","r","4","s","t","u","v","w","x","y","z"]
    inp = raw_input("What phrase would you like to Change?: ")
    key1 = key()
    phrase = inp.split()
    for i in phrase:
        i = i.lower()
        splitword  = list(i)
        for a in range(len(splitword)):
            for c in range(35):
                if splitword[a] == alphabet[c]:
                    if eord == 1: #if you chose to encrypt
                        letter = c + key1 #the new position is created by adding the key to the position of the letter in the alphabet
                    elif eord == 0: # if you chose to decrypt
                        letter = c - key1 # the actual position of the letter is determined
                    #out of bounds checks
                    if letter > 35:
                        letter = letter - 35
                    elif letter < 0:
                        letter = 35 + letter
                    output += str(alphabet[letter]) #appends newly generated encryption/decryption to the overall output


    print output # does what it says on the tin

print("Welcome to encryption service v0.1")
resp1= raw_input("Would you like to encrypt or decrypt: ")
resp1 = resp1.lower()
if resp1 == "encrypt" or resp1 == "e":
    encrypt(1)
elif resp1 == "decrypt" or resp1 == "d":
    encrypt(0)