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def asknewguest():
    choice = input("Would you like to ADD or VIEW a guest, VIEW ALL guests, or EXIT?").upper()
    if choice.islpha() == True: 
        if choice == "ADD":
            enter_new_guest()
        elif choice == "VIEW":
            callinfo()
        elif choice == "VIEW ALL":
            print(guest_list)
            asknewguest()
        elif choice == "EXIT":
            byebye()
        else:
            print("Sorry, I didn't understand that. Please try again.")
            asknewguest()
    else:
        print("Sorry, only alphabetical values are accepted. Please try again.")
        asknewguest()