code: def setUp(self):
      self.batch = CBInput(
          context_arm_features=torch.tensor(
              [
                  [
                      [1, 2],
                      [1, 3],
                  ],
                  [
                      [1, 4],
                      [1, 5],
                  ],
              ],
              dtype=torch.float,
          ),
          action=torch.tensor([[0], [1]], dtype=torch.long),
          reward=torch.tensor([[1.5], [2.3]], dtype=torch.float),
          weight=torch.tensor([[7], [5]], dtype=torch.float),
          action_log_probability=torch.log(
              torch.tensor([[0.5], [0.5]], dtype=torch.float)
          ),
      )
  
file_path: ReAgent/reagent/test/evaluation/cb/test_utils.py
imports: import unittest
  import numpy.testing
  import torch
  from reagent.core.types import CBInput
  from reagent.evaluation.cb.utils import add_importance_weights
label_desc: Use image node_id 1 for calling the TestCBEvalUtils obj's underlying member method code with example usage: obj.setUp() without return types