Backport PR
#9868: Remove access to 'savefig.dpi', use figure.dpi...
Backport PR
#9868: Remove access to 'savefig.dpi', use figure.dpi
`ipykernel` now uses `figure.dpi` to control the dpi of the
image to be created. This means that `dpi` property of the
figure object is a reliable source of truth for the users
preferences.
Depends on ipython/ipykernel/pull/176