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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 index_of_coincidence(*texts):
 """Calculate the index of coincidence for one or more ``texts``. The results are averaged over multiple texts to return the delta index of coincidence. Examples: 0.2 0.2 Args: *texts (variable length argument list):
 The texts to analyze Returns: Decimal value of the index of coincidence Raises: ValueError: If texts is empty ValueError: If any text is less that 2 character long """

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

    return statistics.mean(_calculate_index_of_coincidence(frequency_analyze(text), len(text)) for text in texts)