code: def preprocess(self, data, char_vocab, pos_vocab, args):
      processed = []
      for d in data:
          edit_type = edit.EDIT_TO_ID[edit.get_edit_type(d[0], d[2])]
          src = list(d[0])
          src = [constant.SOS] + src + [constant.EOS]
          src = char_vocab.map(src)
          pos = d[1]
          pos = pos_vocab.unit2id(pos)
          tgt = list(d[2])
          tgt_in = char_vocab.map([constant.SOS] + tgt)
          tgt_out = char_vocab.map(tgt + [constant.EOS])
          processed += [[src, tgt_in, tgt_out, pos, edit_type, d[0]]]
      return processed
  
imports: import random
  import numpy
  import os
  from collections import Counter
  import logging
  import torch
  import stanza.models.common.seq2seq_constant
  from stanza.models.common.data import map_to_ids, get_long_tensor, get_float_tensor, sort_all
  from stanza.models.lemma.vocab import Vocab, MultiVocab
  from stanza.models.lemma import edit
  from stanza.models.common.doc import *
label_desc: Use image node_id 3 for calling the DataLoader obj's underlying member method code with example usage: obj.preprocess(data, char_vocab, pos_vocab, args) and returns: processed