code: def get_collate_fn(self):
      return partial(my_collate_fn, some_arg=2)
  
imports: import numpy
  import pytest
  import torch
  from pytorch_toolbelt.inference.functional import unpad_xyxy_bboxes, pad_image_tensor, unpad_image_tensor, pad_tensor_to_size
  from pytorch_toolbelt.modules.encoders import make_n_channel_input
  from pytorch_toolbelt.utils import match_bboxes, match_bboxes_hungarian, get_collate_for_dataset
  from torch import nn
  from torch.utils.data import ConcatDataset
  from functools import partial
label_desc: Use image node_id 2 for calling the DummyDataset2 obj's underlying member method code with example usage: obj.get_collate_fn() and returns: partial