code: def load_textline_dataset(paths, column_num):
      """Load raw data for text task."""
      ds = tf.data.TextLineDataset(paths)
      ds = ds.map(
          lambda x: tf.squeeze(
              tf.strings.split(x, sep="\t", result_type="RaggedTensor"),
              axis=0,
          )
      )
      ds = ds.filter(lambda line: tf.equal(tf.size(line), column_num))
      ds_list = []
      for i in range(column_num):
          ds_list.append(ds.map(lambda x: x[i]))
  
      return tuple(ds_list)
  
file_path: delta/delta/data/preprocess/text_ops.py
imports: import delta.compat
  from absl import logging
  from delta import utils
  from core.ops import py_x_ops
  from delta.data.utils import read_lines_from_text_file
label_desc: Use image node_id 6 for calling a global function with example usage: load_textline_dataset(paths, column_num) and returns: tuple