class_docstr: Function to score different max_partitions_contributed bounds.
  
  Suitable only for COUNT and PRIVACY_ID_COUNT aggregations.
code: def _max_partitions_contributed_best_upper_bound(self):
      return min(
          self._params.max_partitions_contributed_upper_bound,
          self._number_of_partitions,
      )
  
imports: from dataclasses import dataclass
  from functools import lru_cache
  from typing import List
  import pipeline_dp
  from pipeline_dp import dp_computations
  from pipeline_dp.dataset_histograms.histograms import Histogram
  from pipeline_dp import pipeline_functions
label_desc: Use image node_id 3 for calling the L0ScoringFunction obj's underlying member method code with example usage: obj._max_partitions_contributed_best_upper_bound() and returns: min