Error on notebook.py with inconsistent and DEFAULT_STATIC_FILES_PATH.

[catafest]

I got this error but I cannot figure how to fix it ( some similar errors about from notebook import DEFAULT_STATIC_FILES_PATH can be found on web):

C:\Python364>jupyter-book create mybookname --demo
Traceback (most recent call last):
  File "c:\python364\lib\runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "c:\python364\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Python364\Scripts\jupyter-book.exe\__main__.py", line 5, in <module>
    main()
  File "c:\python364\lib\site-packages\jupyter_book\main.py", line 10, in <module>
    from .build import build_book
  File "c:\python364\lib\site-packages\jupyter_book\build.py", line 8, in <module>
    from nbclean import NotebookCleaner
  File "c:\python364\lib\site-packages\nbclean\__init__.py", line 5, in <module>
    from .clean import NotebookCleaner
  File "c:\python364\lib\site-packages\nbclean\clean.py", line 4, in <module>
    from nbgrader.preprocessors import ClearSolutions
  File "c:\python364\lib\site-packages\nbgrader\preprocessors\__init__.py", line 1, in <module>
    from .base import NbGraderPreprocessor
  File "c:\python364\lib\site-packages\nbgrader\preprocessors\base.py", line 1, in <module>
    from nbconvert.preprocessors import Preprocessor
  File "c:\python364\lib\site-packages\nbconvert\__init__.py", line 6, in <module>
    from . import preprocessors
  File "c:\python364\lib\site-packages\nbconvert\preprocessors\__init__.py", line 7, in <module>
    from .csshtmlheader import CSSHTMLHeaderPreprocessor
  File "c:\python364\lib\site-packages\nbconvert\preprocessors\csshtmlheader.py", line 17, in <modul
e>
    from notebook import DEFAULT_STATIC_FILES_PATH
  File "c:\python364\notebook.py", line 56
    return b
           ^
TabError: inconsistent use of tabs and spaces in indentation

[catafest]

Fixed (by common error):
I have an old notebook.py created by me and this create a conflict error with jupyter_book python module.