code: def get_keep_score(source_counts, prediction_counts, target_counts):
      """Compute the keep score (Equation 5 in the paper)."""
      source_and_prediction_counts = source_counts & prediction_counts
      source_and_target_counts = source_counts & target_counts
      true_positives = sum(
          (
              source_and_prediction_counts & source_and_target_counts
          ).values()
      )
      selected = sum(source_and_prediction_counts.values())
      relevant = sum(source_and_target_counts.values())
      return _get_fbeta_score(true_positives, selected, relevant)
  
file_path: tensor2tensor/tensor2tensor/utils/sari_hook.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  import numpy
  import tensorflow.compat.v1
label_desc: Use image node_id 4 for calling a global function with example usage: get_keep_score(source_counts, prediction_counts, target_counts) and returns: _get_fbeta_score