code: def test_initialize_power_prior(self):
      kernel = LinearTruncatedFidelityKernel(
          fidelity_dims=[1, 2],
          dimension=3,
          power_prior=NormalPrior(1, 1),
      )
      self.assertTrue(isinstance(kernel.power_prior, NormalPrior))
  
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 8 for calling the TestLinearTruncatedFidelityKernel obj's underlying member method code with example usage: obj.test_initialize_power_prior() without return types