docstr: Make sure the loocv works without batching.
docstr_tok: ["Make","sure","the","loocv","works","without","batching","."]
code: def test_smoke_batch(self):
      """Make sure the loocv works without batching."""
      train_x, train_y, loocv = self.get_data([3, 3, 3, 5, 2])
      output = loocv.model(train_x)
      loss = -loocv(output, train_y)
      assert loss.shape == (3, 3, 3)
      loss.sum().backward()
      self.assertTrue(train_x.grad is not None)
  
file_path: gpytorch/test/mlls/test_leave_one_out_pseudo_likelihood.py
imports: import math
  import unittest
  import torch
  import gpytorch
label_desc: Use image node_id 3 for calling the TestLeaveOneOutPseudoLikelihood obj's underlying member method code with example usage: obj.test_smoke_batch() without return types