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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 drift(data, n=3, **kwargs):
 """The drift forecast for the next point is a linear extrapolation from the previous ``n`` points in the series. Args: data (np.array):
 Observed data, presumed to be ordered in time. n (int):
 period over which to calculate linear model for extrapolation Returns: float: a single-valued forecast for the next value in the series. """

    yi = data[-n]
    yf = data[-1]
    slope = (yf - yi) / (n - 1)
    forecast = yf + slope
    return forecast