docstr: `Dictionary` can be saved as textfile and loaded again from textfile. 
code: def test_saveAsText_and_loadFromText(self):
      """`Dictionary` can be saved as textfile and loaded again from textfile."""
      tmpf = get_tmpfile("dict_test.txt")
      for sort_by_word in [True, False]:
          d = Dictionary(self.texts)
          d.save_as_text(tmpf, sort_by_word=sort_by_word)
          self.assertTrue(os.path.exists(tmpf))
  
          d_loaded = Dictionary.load_from_text(tmpf)
          self.assertNotEqual(d_loaded, None)
          self.assertEqual(d_loaded.token2id, d.token2id)
  
imports: from collections.abc import Mapping
  from itertools import chain
  import logging
  import unittest
  import codecs
  import os
  import os.path
  import scipy
  import gensim
  from gensim.corpora import Dictionary
  from gensim.utils import to_utf8
  from gensim.test.utils import get_tmpfile, common_texts
label_desc: Use image node_id 19 for calling the TestDictionary obj's underlying member method code with example usage: obj.test_saveAsText_and_loadFromText() without return types