def METHOD_NAME(self):
    # for example, character models treat space as a symbol
    dict_file = io.StringIO("  999\n" "a 999\n" "b 999\n")
    d = Dictionary()
    d.add_from_file(dict_file)
    self.assertEqual(d.index(" "), 4)
    self.assertEqual(d.index("a"), 5)
    self.assertEqual(d.index("b"), 6)