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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 _sec_to_readable(t):
 """Convert a number of seconds to a more readable representation."""

    # This will only work for < 1 day execution time
    # And we reserve 2 digits for minutes because presumably
    # there aren't many > 99 minute scripts, but occasionally some
    # > 9 minute ones
    t = datetime(1, 1, 1) + timedelta(seconds=t)
    t = '{0:02d}:{1:02d}.{2:03d}'.format(
        t.hour * 60 + t.minute, t.second,
        int(round(t.microsecond / 1000.)))
    return t