docstr: Tokenize a string. 
docstr_tok: ["Tokenize","a","string","."]
code: def text_to_tokens(self, text):
      """Tokenize a string."""
      tokens = []
      rows = text.split(NEW_LINE)
      num_rows = len(rows)
      for row_id in range(num_rows):
          row = rows[row_id]
          if row == "":
              continue
          fields = row.split(self.delimiter)
          for f in fields:
              splits = f.split(END_OF_TEXT)
              if len(splits) == 1:
                  tokens.append(f.strip())
              elif len(splits) == 2:
                  if splits[0] != "":
                      tokens.append(splits[0].strip())
                  tokens.append(END_OF_TEXT)
                  if splits[1] != "":
                      tokens.append(splits[1].strip())
              else:
                  raise ValueError("delimiter error")
          if row_id != num_rows - 1:
              tokens.append(NEW_LINE)
      return tokens
  
imports: import pickle
  from typing import List
  import numpy
  from nemo.collections.common.tokenizers.column_coder import ColumnCodes
  from nemo.collections.common.tokenizers.tokenizer_spec import TokenizerSpec
label_desc: Use image node_id 9 for calling the TabularTokenizer obj's underlying member method code with example usage: obj.text_to_tokens(text) and returns: tokens