code: def collate_single(self, batch):
      assert (
          len(batch) == 1
      ), "Currently we do not support batched training"
      return batch[0]
  
imports: import os
  import pickle
  import random
  import matplotlib.pyplot
  import networkx
  from torch.utils.data import Dataset
label_desc: Use image node_id 4 for calling the CycleDataset obj's underlying member method code with example usage: obj.collate_single(batch) and returns: batch