Caesar Cipher

import a

coded=[]
choice="y"
l_alpha=list(string.ascii_lowercase)
u_alpha=list(string.ascii_uppercase)

#Function to Encrypt
def encryption(sentence):
    for i in sentence:
        if i in l_alpha:
            id=l_alpha.index(i)-3
            coded.append(l_alpha[id])

        elif i in u_alpha:
            id=u_alpha.index(i)-3
            coded.append(u_alpha[id])

        elif not i.isalpha():
            coded.append(i)

    encrypted="".join(coded)

    print(encrypted)

#Function to Decrypt
def decryption(sentence):
    for i in sentence:
        if i in l_alpha:
            id=l_alpha.index(i)
            if id>22:
                id=id-23
                coded.append(l_alpha[id])
            else:
                id+=3
                coded.append(l_alpha[id])

        elif i in u_alpha:
            id=u_alpha.index(i)
            if id>22:
                id=id-23
                coded.append(u_alpha[id])
            else:
                id+=3
                coded.append(u_alpha[id])

        elif not i.isalpha():
            coded.append(i)

        decrypted="".join(coded)

    print(decrypted)


while (choice != "Q" or choice !="q"):
    choice=input("What would you like to do?\nPress 'A': To encrypt a message\nPress 'B': To decrypt a message\n ")

    if (choice == "A" or choice == "a"):
        print()
        message=input("Enter the sentence you would like to encrypt: ")
        print(f"Your message has been encrpted to: ", end="")
        encryption(message)
        print("\nYou may press 'Q' to quit")
        print()

    elif (choice=="B" or choice == "b"):
        print()
        message=input("Enter the sentence you would like to decrypt: ")
        print(f"Your message has been decrypted. Your original message was: ", end="")
        decryption(message)
        print("\nYou may press 'Q' to quit")
        print()

    elif (choice =="Q" or choice == 'q'):
        print()
        print("Thank you. Pls stay safe!")
        break

    else:
        print("That was a wrong choice. You can simply press 'Q' to Quit")
        print()