code: def split(self, json_line):
      data = json.loads(json_line)
      output = {}
      for key in self.args.json_keys:
          text = data[key]
          max_len = 1000000
          tokens_list = [
              Encoder.splitter.tokenize(text[i : i + max_len])
              for i in range(0, len(text), max_len)
          ]
          output[key] = [
              tokens for partial in tokens_list for tokens in partial
          ]
      return json.dumps(output), len(json_line)
  
imports: import argparse
  import math
  import json
  import os
  import sys
  import time
  import gzip
  import glob
  import torch
  import numpy
  import multiprocessing
  from megatron.tokenizer import build_tokenizer
  from megatron.core.datasets import indexed_dataset
label_desc: Use image node_id 3 for calling the Encoder obj's underlying member method code with example usage: obj.split(json_line) and returns: json,  len