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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def ask_string(*question: Token, default: Optional[str] = None) -> Optional[str]: """Ask the user to enter a string. """

    tokens = get_ask_tokens(question)
    if default:
        tokens.append("(%s)" % default)
    info(*tokens)
    answer = read_input()
    if not answer:
        return default
    return answer