How to determine the module name to filter a specific Python warning?

With Python one can filter specific warnings using the following command line syntax:

-W action:message:category:module:line

But how can one determine the correct value for module for a particular warning?

Consider the following example:

Using (pipenv --python 3.6.5 install lxml==4.2.4)

> python -W error -c "from lxml import etree"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "src/lxml/etree.pyx", line 75, in init lxml.etree
  File "src/lxml/_elementpath.py", line 56, in init lxml._elementpath
ImportWarning: can't resolve package from __spec__ or __package__, falling back on __name__ and __path__

If one wanted to ignore only that specific import warning, how does one find the module name to use? None of the following commands appear to be correct. They all still emit the warning.

python -W error -W ignore::ImportWarning:lxml -c "from lxml import etree"
python -W error -W ignore::ImportWarning:lxml.etree -c "from lxml import etree"
python -W error -W ignore::ImportWarning:lxml._elementpath -c "from lxml import etree"
python -W error -W ignore::ImportWarning:etree -c "from lxml import etree"
python -W error -W ignore::ImportWarning:_elementpath -c "from lxml import etree"
python -W error -W 'ignore::ImportWarning:lxml[.*]' -c "from lxml import etree"

from How to determine the module name to filter a specific Python warning?