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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 price_oscillator(data, short_period, long_period):
 """ Price Oscillator. Formula: (short EMA - long EMA / long EMA) * 100 """

    catch_errors.check_for_period_error(data, short_period)
    catch_errors.check_for_period_error(data, long_period)

    ema_short = ema(data, short_period)
    ema_long = ema(data, long_period)

    po = ((ema_short - ema_long) / ema_long) * 100
    return po