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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 average_true_range_percent(close_data, period):
 """ Average True Range Percent. Formula: ATRP = (ATR / CLOSE) * 100 """

    catch_errors.check_for_period_error(close_data, period)
    atrp = (atr(close_data, period) / np.array(close_data)) * 100
    return atrp