code: def splits(
          cls,
          conn_str,
          candidate_def,
          word_dict=None,
          train=0,
          dev=1,
          test=2,
          use_lfs=(0, 0, 0),
          pretrained_word_dict=None,
          max_seq_len=125,
      ):
          
          # initialize word_dict if needed
          train_set = cls(
              conn_str,
              candidate_def,
              word_dict=word_dict,
              split=train,
              use_lfs=use_lfs[train],
              pretrained_word_dict=pretrained_word_dict,
              max_seq_len=max_seq_len,
          )
          return (
              train_set,
              cls(
                  conn_str,
                  candidate_def,
                  word_dict=train_set.word_dict,
                  split=dev,
                  use_lfs=use_lfs[dev],
                  max_seq_len=max_seq_len,
              ),
              cls(
                  conn_str,
                  candidate_def,
                  word_dict=train_set.word_dict,
                  split=test,
                  use_lfs=use_lfs[test],
                  max_seq_len=max_seq_len,
              ),
          )
docs: Create train/dev/test splits (mapped to split numbers)
  
          :param conn_str:
          :param candidate_def:
          :param word_dict:
          :param train:
          :param dev:
          :param test:
          :param use_lfs:
          :param pretrained_word_dict:
          :param max_seq_len:
          :return: