code: def forward(self, x):
      mean_x = self.mean_module(x)
      covar_x = self.covar_module(x)
      return gpytorch.distributions.MultivariateNormal(mean_x, covar_x)
  
imports: import math
  import os
  import random
  import unittest
  import warnings
  import torch
  from torch import optim
  import gpytorch
  from gpytorch.test.utils import least_used_cuda_device
  from gpytorch.utils.warnings import GPInputWarning
label_desc: Use image node_id 2 for calling the GridGPRegressionModel obj's underlying member method code with example usage: obj.forward(x) and returns: gpytorch