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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 triangular_moving_average(data, period):
 """ Triangular Moving Average. Formula: TMA = SMA(SMA()) """

    catch_errors.check_for_period_error(data, period)

    tma = sma(sma(data, period), period)
    return tma