class_docstr: Positional dropping used in MSN (https://arxiv.org/pdf/2204.07141.pdf)
code: def test_msn_pos_drop(self) -> None:
      config = self.pretraining_config()
      model = build_model(config["MODEL"], config["OPTIMIZER"])
      x = torch.randn(size=(2, 3, 224, 224))
      y = model(x)[0]
      self.assertEqual(x.shape[0], y.shape[0], "Same batch size")
      self.assertEqual(y.shape[1], 1024, "Number of prototypes")
  
file_path: vissl/tests/test_msn.py
imports: import unittest
  import torch
  from vissl.models import build_model
  from vissl.utils.hydra_config import compose_hydra_configuration, convert_to_attrdict
  from vissl.utils.test_utils import gpu_test, in_temporary_directory, run_integration_test
label_desc: Use image node_id 2 for calling the TestMSN obj's underlying member method code with example usage: obj.test_msn_pos_drop() without return types