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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 pearson_correlation_coefficient(predictions, labels, weights_fn=None):
 """Calculate pearson correlation coefficient. Args: predictions: The raw predictions. labels: The actual labels. weights_fn: Weighting function. Returns: The pearson correlation coefficient. """

  del weights_fn
  _, pearson = tf.contrib.metrics.streaming_pearson_correlation(predictions,
                                                                labels)
  return pearson, tf.constant(1.0)