class_docstr: Test loss functions.
class_docstr_tok: ["Test","loss","functions","."]
docstr: Test HuberLoss.
code: def test_huber_loss_pytorch(self):
      """Test HuberLoss."""
      loss = losses.HuberLoss()
      outputs = torch.tensor([[0.1, 0.8], [0.4, 0.6]])
      labels = torch.tensor([[1.0, -1.0], [-1.0, 1.0]])
      result = np.mean(
          loss._create_pytorch_loss()(outputs, labels).numpy()
      )
      expected = 0.67125
      assert np.allclose(expected, result)
  
imports: import unittest
  import numpy
  import pytest
  import deepchem
  import deepchem.models.losses
label_desc: Use image node_id 4 for calling the TestLosses obj's underlying member method code with example usage: obj.test_huber_loss_pytorch() without return types