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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 upper_price_channel(data, period, upper_percent):
 """ Upper Price Channel. Formula: upc = EMA(t) * (1 + upper_percent / 100) """

    catch_errors.check_for_period_error(data, period)

    emas = ema(data, period)
    upper_channel = [val * (1+float(upper_percent)/100) for val in emas]
    return upper_channel