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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 computeEntropy(spikeTrains):
 """ Estimates entropy in spike trains. @param spikeTrains (array) matrix of spike trains @return entropy (float) entropy """

  MIN_ACTIVATION_PROB = 0.000001
  activationProb = np.mean(spikeTrains, 1)
  activationProb[activationProb < MIN_ACTIVATION_PROB] = MIN_ACTIVATION_PROB
  activationProb = activationProb / np.sum(activationProb)
  entropy = -np.dot(activationProb, np.log2(activationProb))
  return entropy