Traceback (most recent call last):

  File "D:/pycode/data_preprocessing/extractTxt.py", line 66, in <module>

    files2txt(filepath1)

  File "D:/pycode/data_preprocessing/extractTxt.py", line 26, in files2txt

    new2txtpath = os.path.join(savepath, new_name)

  File "C:\Program Files\Python38\lib\ntpath.py", line 109, in join

    genericpath._check_arg_types('join', path, *paths)

  File "C:\Program Files\Python38\lib\genericpath.py", line 152, in _check_arg_types

    raise TypeError('%s() argument must be str or bytes, not %r' %

TypeError: join() argument must be str or bytes, not 'NoneType'