code: def test_memory_leak():
      with torch.no_grad():  # remove a warning
          param = torch.rand((2, 3), requires_grad=True)
          param.grad = torch.rand(2, 3)
  
          bucket = GradBucket(300, param.dtype, param.device, -1)
          bucket.add_grad(param)
          bucket.shrink()
  
          storage = bucket.buffer.storage()
          # See https://github.com/pytorch/pytorch/pull/59671/
          if hasattr(storage, "nbytes"):
              assert (
                  storage.nbytes() == 6 * bucket.buffer.element_size()
              )
          else:
              assert len(storage) == 6
  
imports: import pytest
  import torch
  from fairscale.nn.misc import GradBucket
label_desc: Use image node_id 2 for calling a global function with example usage: test_memory_leak() without return types