Access to exception message with str(error.value) Cf. https://github.com/pytest-dev/pytest/issues/5528
Access to exception message with str(error.value)
Cf. https://github.com/pytest-dev/pytest/issues/5528

Fixes #269

mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext