code: def test_active_dims_list(self):
      kernel = LinearTruncatedFidelityKernel(
          fidelity_dims=[1, 2], dimension=10, active_dims=[0, 2, 4, 6]
      )
      x = self.create_data_no_batch()
      covar_mat = kernel(x).evaluate_kernel().to_dense()
      kernel_basic = LinearTruncatedFidelityKernel(
          fidelity_dims=[1, 2], dimension=4
      )
      covar_mat_actual = (
          kernel_basic(x[:, [0, 2, 4, 6]]).evaluate_kernel().to_dense()
      )
      self.assertLess(
          torch.linalg.norm(covar_mat - covar_mat_actual)
          / covar_mat_actual.norm(),
          1e-4,
      )
  
imports: import itertools
  import torch
  from botorch.exceptions import UnsupportedError
  from botorch.models.kernels.linear_truncated_fidelity import LinearTruncatedFidelityKernel
  from botorch.utils.testing import BotorchTestCase
  from gpytorch.kernels.matern_kernel import MaternKernel
  from gpytorch.kernels.rbf_kernel import RBFKernel
  from gpytorch.priors.torch_priors import GammaPrior, NormalPrior
  from gpytorch.test.base_kernel_test_case import BaseKernelTestCase
label_desc: Use image node_id 12 for calling the TestLinearTruncatedFidelityKernel obj's underlying member method code with example usage: obj.test_active_dims_list() without return types