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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 _user_input() -> str: """ A helper function which waits for user multi-line input. :return: A string input by user, separated by ``'\\n'``. """


    lines = []
    try:
        while True:
            line = input()
            if line != '':
                lines.append(line)
            else:
                break
    except (EOFError, KeyboardInterrupt):
        return '\n'.join(lines)