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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 convert_time_units(t):
 """ Convert time in seconds into reasonable time units. """

    if t == 0:
        return '0 s'
    order = log10(t)
    if -9 < order < -6:
        time_units = 'ns'
        factor = 1000000000
    elif -6 <= order < -3:
        time_units = 'us'
        factor = 1000000
    elif -3 <= order < -1:
        time_units = 'ms'
        factor = 1000.
    elif -1 <= order:
        time_units = 's'
        factor = 1
    return "{:.3f} {}".format(factor * t, time_units)