Update tokenization_character_bert.py

tokenization_character_bert.py

@@ -23,7 +23,7 @@ from typing import Dict, List, Optional, Tuple, Union
 
 import numpy as np
 
-from transformers.file_utils import _is_tensorflow, _is_torch, is_tf_available, is_torch_available, to_py_obj
+from transformers.file_utils import is_tf_available, is_torch_available, to_py_obj
 from transformers.tokenization_utils import (
     BatchEncoding,
     EncodedInput,