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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 abs_energy(x):
 """ Returns the absolute energy of the time series which is the sum over the squared values .. math:: E = \\sum_{i=1,\ldots, n} x_i^2 :param x: the time series to calculate the feature of :type x: numpy.ndarray :return: the value of this feature :return type: float """

    if not isinstance(x, (np.ndarray, pd.Series)):
        x = np.asarray(x)
    return np.dot(x, x)