travis-list.py

known_users = ["Alice", "Bob","claire","Dan","Emma","Fred","Georgie","Harry"]

print(len(known_users))

while True:
    print("Hi! My name is Travis")

    name = input("What is your name?:").strip().capitalize()

    if name in known_users:
        print("Hello {}!".format(name))

        remove = input("Would you like to be removed from the system (y/n)?:").strip().lower()
        if remove == "y":
            known_users.remove(name)
            print(known_users)
        elif remove == "n":
            print("No problem, I didn't want you to leave anyway!")
        
    else:
        print("Hmmm I don't think you in the database, {}".format(name))

        add_me = input("Would you like to be aded to the system (y/n)?:").strip().lower()
        if add_me == "y":
            known_users.append(name)
            print(known_users)
        elif add_me == "n":
            print("No worries, see you around")