code: def create_kernel_ard(self, num_dims, **kwargs):
      return RFFKernel(
          num_dims=num_dims,
          num_samples=7,
          ard_num_dims=num_dims,
          **kwargs,
      )
  
imports: import unittest
  from unittest.mock import MagicMock, patch
  import linear_operator
  import torch
  import gpytorch
  from gpytorch.kernels import RFFKernel
  from gpytorch.test.base_kernel_test_case import BaseKernelTestCase
label_desc: Use image node_id 2 for calling the TestRFFKernel obj's underlying member method code with example usage: obj.create_kernel_ard(num_dims) and returns: RFFKernel