code: def test_joint_exact_counts(self):
      match_groups = ["joint_a_cl"]
      self.check_group_counts(
          "joint_a_cl", "exact", match_groups, metric_type="joint"
      )
  
imports: import unittest
  from copy import deepcopy
  from finetune.util.group_metrics import get_count_fn, calc_group_assignment, create_joint_groups, get_metrics, group_metrics, joint_metrics
label_desc: Use image node_id 7 for calling the TestGroupMetricCountFunctions obj's underlying member method code with example usage: obj.test_joint_exact_counts() without return types