$ py.test tests --pdb                         jdaviz-dev
=============================== test session starts ================================
platform darwin -- Python 3.7.10, pytest-6.1.2, py-1.10.0, pluggy-0.13.1
rootdir: /Users/maartenbreddels/src/bqplot, configfile: pytest.ini
plugins: asdf-2.8.0, anyio-3.0.1
collected 10 items                                                                 

tests/binary_serialization_test.py .....                                     [ 50%]
tests/marks_test.py ....                                                     [ 90%]
tests/selector_test.py .                                                     [100%]

================================= warnings summary =================================
../../miniconda3/envs/jdaviz-dev/lib/python3.7/site-packages/traittypes/traittypes.py:24
  /Users/maartenbreddels/miniconda3/envs/jdaviz-dev/lib/python3.7/site-packages/traittypes/traittypes.py:24: DeprecationWarning: 
              Sentinel is not a public part of the traitlets API.
              It was published by mistake, and may be removed in the future.
              
    """)

-- Docs: https://docs.pytest.org/en/stable/warnings.html
========================== 10 passed, 1 warning in 0.19s ===========================