来自traceback import format_exception_only ImportError：无法导入名称'format_exception_only'

Question

from nltk.tokenize import sent_tokenize, word_tokenize
example_txt= "Hello, My name is Akash. The weather is good and python is Awesome."

print(sent_tokenize(example_txt))
print("=====================================")
print(word_tokenize(example_txt))    
print("=====================================")

for i in word_tokenize(example_txt):
    print(i)

错误： 当我试图运行该程序时，它给我一个错误，我应该怎么做？

Traceback (most recent call last):
  File "A:/Sem 2/Testing_project/NLP_NLTK_Sentdex/tokenize.py", line 1, in <module>
    from nltk.tokenize import sent_tokenize, word_tokenize
  File "C:\Users\Akash\Anaconda3\lib\site-packages\nltk\__init__.py", line 89, in <module>
    from nltk.internals import config_java
  File "C:\Users\Akash\Anaconda3\lib\site-packages\nltk\internals.py", line 11, in <module>
    import subprocess
  File "C:\Users\Akash\Anaconda3\lib\subprocess.py", line 126, in <module>
    import threading
  File "C:\Users\Akash\Anaconda3\lib\threading.py", line 7, in <module>
    from traceback import format_exc as _format_exc
  File "C:\Users\Akash\Anaconda3\lib\traceback.py", line 5, in <module>
    import linecache
  File "C:\Users\Akash\Anaconda3\lib\linecache.py", line 11, in <module>
    import tokenize
  File "A:\Sem 2\Testing_project\NLP_NLTK_Sentdex\tokenize.py", line 1, in <module>
    from nltk.tokenize import sent_tokenize, word_tokenize
  File "C:\Users\Akash\Anaconda3\lib\site-packages\nltk\tokenize\__init__.py", line 64, in <module>
    from nltk.tokenize.mwe      import MWETokenizer
  File "C:\Users\Akash\Anaconda3\lib\site-packages\nltk\tokenize\mwe.py", line 31, in <module>
    from nltk.util import Trie
  File "C:\Users\Akash\Anaconda3\lib\site-packages\nltk\util.py", line 13, in <module>
    import pydoc
  File "C:\Users\Akash\Anaconda3\lib\pydoc.py", line 72, in <module>
    from traceback import format_exception_only
ImportError: cannot import name 'format_exception_only'