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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 timedelta_average(*values: datetime.timedelta) -> datetime.timedelta: r"""Compute the arithmetic mean for timedeltas list. :param \*values: Timedelta instances to process. """

    if isinstance(values[0], (list, tuple)):
        values = values[0]
    return sum(values, datetime.timedelta()) // len(values)