text: import pytest
  import torch
  
  from model import MyCNN
  
  
  @pytest.fixture
  def model(const):
      return MyCNN(
          num_channel=const["NUM_CHANNEL"],
          num_class=const["NUM_CLASSES"],
          chunk_size=const["DURATION"]
      )
  
  
  def test_MyCNN_forward(model, const):
  
      dummy = torch.rand(1, const["NUM_CHANNEL"], const["DURATION"])
      output = model.forward(dummy)
      assert output.shape == (1, const["NUM_CLASSES"])
  
  
  def test_MyCNN_step(model, const, helpers):
  
      fake_batch = helpers.simulate_ecg_signal(const["DURATION"])
      fake_batch["label"] = torch.from_numpy(fake_batch["label"]).unsqueeze(0)
      loss, y_pred, y = model.step(fake_batch, 0)
      assert loss is not None
      assert y_pred.shape == y.shape
  