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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_to_duration(dt):
 """ Return a string according to the DURATION property format from a timedelta object """

    days, secs = dt.days, dt.seconds
    res = 'P'
    if days // 7:
        res += str(days // 7) + 'W'
        days %= 7
    if days:
        res += str(days) + 'D'
    if secs:
        res += 'T'
        if secs // 3600:
            res += str(secs // 3600) + 'H'
            secs %= 3600
        if secs // 60:
            res += str(secs // 60) + 'M'
            secs %= 60
        if secs:
            res += str(secs) + 'S'
    return res