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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 rasterPlot(spikeTrain, model):
 """ Plots raster and saves figure in working directory @param spikeTrain (array) matrix of spike trains @param model (string) string specifying the name of the origin of the spike trains for the purpose of concatenating it to the filename (either TM or Poisson) """

  nTrials = np.shape(spikeTrain)[0]
  spikes = []
  for i in range(nTrials):
    spikes.append(spikeTrain[i].nonzero()[0].tolist())
  plt.figure()
  ax = raster(spikes)
  plt.xlabel('Time')
  plt.ylabel('Neuron')
  # plt.show()
  plt.savefig("raster" + str(model))
  plt.close()