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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_isoformat(td: datetime.timedelta) -> str: """ ISO 8601 encoding for timedeltas. """

    minutes, seconds = divmod(td.seconds, 60)
    hours, minutes = divmod(minutes, 60)
    return f'P{td.days}DT{hours:d}H{minutes:d}M{seconds:d}.{td.microseconds:06d}S'