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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 truncate(sequence):
 """ Create a potentially shortened text display of a list. Parameters sequence : list An indexable sequence of elements. Returns ------- str The list as a formatted string. """

    if len(sequence) > LIST_SLICE:
        return ", ".join(sequence[:LIST_SLICE] + ["..."])
    else:
        return ", ".join(sequence)