code: def test_inference_no_head(self):
      model = MegaModel.from_pretrained("mnaylor/mega-base-wikitext")
  
      input_ids = torch.tensor(
          [[0, 31414, 232, 328, 740, 1140, 12695, 69, 46078, 1588, 2]]
      )
      with torch.no_grad():
          output = model(input_ids)[0]
      expected_shape = torch.Size((1, 11, 128))
      self.assertEqual(output.shape, expected_shape)
      # compare the actual values for a slice. taken from output[:, :3, :3]
      expected_slice = torch.tensor(
          [
              [
                  [1.1767, -0.6349, 2.8494],
                  [-0.5109, -0.7745, 1.9495],
                  [-0.3287, -0.2111, 3.3367],
              ]
          ]
      )
  
      self.assertTrue(
          torch.allclose(output[:, :3, :3], expected_slice, atol=1e-4)
      )
  
imports: import unittest
  from transformers import MegaConfig, is_torch_available
  from transformers.testing_utils import TestCasePlus, require_torch, require_torch_fp16, slow, torch_device
  from ...generation.test_utils import GenerationTesterMixin
  from ...test_configuration_common import ConfigTester
  from ...test_modeling_common import ModelTesterMixin, floats_tensor, ids_tensor, random_attention_mask
  from ...test_pipeline_mixin import PipelineTesterMixin
label_desc: Use image node_id 2 for calling the MegaModelIntegrationTest obj's underlying member method code with example usage: obj.test_inference_no_head() without return types