docstr: Tests process with two_three as active.
docstr_tok: ["Tests","process","with","two_three","as","active","."]
code: def test_single_sign(self):
      """
      Tests process with two_three as active.
      """
      atf = ATFConverter(two_three=True)
      signs = ["a", "a1", "a2", "a3", "be2", "be3", "bad2", "bad3"]
      target = ["a", "a₁", "a₂", "a₃", "be₂", "be₃", "bad₂", "bad₃"]
      output = atf.process(signs)
      self.assertEqual(output, target)
  
file_path: cltk/tests/test_text.py
imports: import unittest
  from unittest.mock import patch
  from cltk.text.akk import ATFConverter
label_desc: Use image node_id 1 for calling the TestAkkadianUtils obj's underlying member method code with example usage: obj.test_single_sign() without return types