code: def gen_uniform_20_20_60_split(data):
      skf = StratifiedKFold(5, shuffle=True, random_state=55)
      idx = [torch.from_numpy(i) for _, i in skf.split(data.y, data.y)]
      data.train_idx = idx[0].to(torch.long)
      data.val_idx = idx[1].to(torch.long)
      data.test_idx = torch.cat(idx[2:], dim=0).to(torch.long)
      return data
  
file_path: pytorch_geometric/examples/dna.py
imports: import os.path
  import torch
  import torch.nn.functional
  from sklearn.model_selection import StratifiedKFold
  from torch_geometric.datasets import Planetoid
  from torch_geometric.nn import DNAConv
label_desc: Use image node_id 1 for calling a global function with example usage: gen_uniform_20_20_60_split(data) and returns: data