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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 extract_energy(rate, sig):
 """ Extracts the energy of frames. """


    mfcc = python_speech_features.mfcc(sig, rate, appendEnergy=True)
    energy_row_vec = mfcc[:, 0]
    energy_col_vec = energy_row_vec[:, np.newaxis]
    return energy_col_vec