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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 score(text, *score_functions):
 """Score ``text`` using ``score_functions``. Examples: Args: text (str):
 The text to score *score_functions (variable length argument list):
 functions to score with Returns: Arithmetic mean of scores Raises: ValueError: If score_functions is empty """

    if not score_functions:
        raise ValueError("score_functions must not be empty")

    return statistics.mean(func(text) for func in score_functions)