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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 _pad(X):
 """ add zeroes on the border to make sure the signal length is a power of two """

    p_above = int(np.floor(np.log2(X.shape[1])))
    M = 2 ** (p_above + 1) - X.shape[1]
    X = np.hstack((np.zeros((X.shape[0], M)), X))

    return X, M