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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 computeISI(spikeTrains):
 """ Estimates the inter-spike interval from a spike train matrix. @param spikeTrains (array) matrix of spike trains @return isi (array) matrix with the inter-spike interval obtained from the spike train. Each entry in this matrix represents the number of time-steps in-between 2 spikes as the algorithm scans the spike train matrix. """

  zeroCount = 0
  isi = []
  cells = 0
  for i in range(np.shape(spikeTrains)[0]):
    if cells > 0 and cells % 250 == 0:
      print str(cells) + " cells processed"
    for j in range(np.shape(spikeTrains)[1]):
      if spikeTrains[i][j] == 0:
        zeroCount += 1
      elif zeroCount > 0:
        isi.append(zeroCount)
        zeroCount = 0
    zeroCount = 0
    cells += 1
  print "**All cells processed**"
  return isi