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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 percent_bandwidth(data, period, std=2.0):
 """ Percent Bandwidth. Formula: %_bw = data() - l_bb() / bb_range() """

    catch_errors.check_for_period_error(data, period)

    period = int(period)
    percent_bandwidth = ((np.array(data) -
                         lower_bollinger_band(data, period, std)) /
                         bb_range(data, period, std)
                         )

    return percent_bandwidth