code: def setUp(self) -> None:
      self.actions = ["A", "B", "C"]
      key = "logged_action"
      self.aggregator = ActionCountAggregator(key, self.actions)
      logged_actions = [
          [
              torch.tensor([0, 0, 1, 2, 2]).unsqueeze(1),
              torch.tensor([0, 1, 1, 2, 2]).unsqueeze(1),
          ],
          [
              torch.tensor([1, 0, 1, 2, 0]).unsqueeze(1),
              torch.tensor([0, 1, 1, 0, 2]).unsqueeze(1),
          ],
      ]
      for x in logged_actions:
          self.aggregator(key, x)
  
file_path: ReAgent/reagent/test/core/aggregators_test.py
imports: import unittest
  import torch
  from reagent.core.aggregators import ActionCountAggregator
label_desc: Use image node_id 1 for calling the ActionCountAggregatorTest obj's underlying member method code with example usage: obj.setUp() without return types