code: def test_forward_mat_multi_batch(self):
      b, n, d = torch.Size([2, 3]), 4, 5
      test_x = torch.randn(*b, n, d)
      mean = self.create_mean(d, b)
      self.assertEqual(mean(test_x).shape, torch.Size([*b, n]))
  
file_path: gpytorch/test/means/test_linear_mean.py
imports: import unittest
  import torch
  from gpytorch.means import LinearMean
  from gpytorch.test.base_mean_test_case import BaseMeanTestCase
label_desc: Use image node_id 5 for calling the TestLinearMean obj's underlying member method code with example usage: obj.test_forward_mat_multi_batch() without return types