code: def _spvec2pow(specvec):
      """Convert a spectrum envelope into a power
  
      Parameters
      ----------
      specvec : vector, shape (`fftlen / 2 + 1`)
          Vector of specturm envelope |H(w)|^2
  
      Return
      ------
      power : scala,
          Power of a frame
  
      """
  
      # set FFT length
      fftl2 = len(specvec) - 1
      fftl = fftl2 * 2
  
      # specvec is not amplitude spectral |H(w)| but power spectral |H(w)|^2
      power = specvec[0] + specvec[fftl2]
      for k in range(1, fftl2):
          power += 2.0 * specvec[k]
      power /= fftl
  
      return power
  
imports: import argparse
  import fnmatch
  import multiprocessing
  import os
  import numpy
  import pysptk
  import pyworld
  import scipy
  from fastdtw import fastdtw
  from scipy.io import wavfile
  from scipy.signal import firwin, lfilter
label_desc: Use image node_id 4 for calling a global function with example usage: _spvec2pow(specvec) and returns: power