def validation_string() -> str:
    """Asks the user to input a validation string

    Returns:
        str: the validation string
    """

    output = input("Please input the wordle hints> ")

    # protect against inputs that contain more or less than 5 characters
    while len(output) != 5:
        print("Input is not a 5 character string!")
        output = input("Please input the wordle hints> ")

    # protect against invalid validation symbols
    while False in [char in "xyg" for char in output]:
        print("Error! Unknown symbol.")
        output = input("Please input the wordle hints> ")

    return output