OK, so obviously one has to ignore the ignore-warning explicitly. One can do this in the pylint config file: if you don't have one, simply generate a standard configuration via
pylint --generate-rcfile > pylint.rc
and uncomment the line with disable=...
and add I0011
to the list. This suppresses all warnings regarding "locally defined disablings".
The other method is to add the following line to the beginning of a file (or block, whatever), if you don't want to suppress the warning globally:
#pylint: disable=I0011