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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 error_rate(predictions, labels):
 """Return the error rate based on dense predictions and 1-hot labels."""

  return 100.0 - (
      100.0 *
      np.sum(np.argmax(predictions, 1) == np.argmax(labels, 1)) /
      predictions.shape[0])