ModuleNotFoundError: No module named 'packaging'

[papr]

nbconvert relies on packaging in nbconvert.utils.version but does not specify packaging as a direct dependency.

Instead, packaging was installed via bleach<5. Starting with version 5, bleach no longer relies on packaging (see mozilla/bleach#621). As a result, nbconvert fails importing packaging in a fresh install.

python3.10 -m venv .venv
source .venv/bin/activate
pip install nbconvert
python -m jupyter nbconvert --to markdown example.ipynb --ExtractOutputPreprocessor.enabled=False

 Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.10.4/x64/bin/jupyter-nbconvert", line 5, in <module>
    from nbconvert.nbconvertapp import main
  File "/opt/hostedtoolcache/Python/3.10.4/x64/lib/python3.10/site-packages/nbconvert/__init__.py", line 4, in <module>
    from .exporters import *
  File "/opt/hostedtoolcache/Python/3.10.4/x64/lib/python3.10/site-packages/nbconvert/exporters/__init__.py", line 3, in <module>
    from .html import HTMLExporter
  File "/opt/hostedtoolcache/Python/3.10.4/x64/lib/python3.10/site-packages/nbconvert/exporters/html.py", line 26, in <module>
    from nbconvert.filters.highlight import Highlight2HTML
  File "/opt/hostedtoolcache/Python/3.10.4/x64/lib/python3.10/site-packages/nbconvert/filters/__init__.py", line 6, in <module>
    from .markdown import *
  File "/opt/hostedtoolcache/Python/3.10.4/x64/lib/python3.10/site-packages/nbconvert/filters/markdown.py", line 23, in <module>
    from .pandoc import convert_pandoc
  File "/opt/hostedtoolcache/Python/3.10.4/x64/lib/python3.10/site-packages/nbconvert/filters/pandoc.py", line 1, in <module>
    from nbconvert.utils.pandoc import pandoc
  File "/opt/hostedtoolcache/Python/3.10.4/x64/lib/python3.10/site-packages/nbconvert/utils/pandoc.py", line 12, in <module>
    from nbconvert.utils.version import check_version
  File "/opt/hostedtoolcache/Python/3.10.4/x64/lib/python3.10/site-packages/nbconvert/utils/version.py", line 11, in <module>
    from packaging.version import Version
ModuleNotFoundError: No module named 'packaging'

Nbconvert version: 6.4.5

The solution would be to add packaging as a requirement.

[ReubenFrankel]

See #1754

[blink1073]

Fixed by #1754