title: How to I dynamically add a pytest marker with my own pytest classes?
body: <p>I want to add some manual markers to the discovered tests I am doing at <a href="https://github.com/pycontribs/pytest-molecule/blob/master/pytest_molecule/__init__.py#L53" rel="nofollow noreferrer">https://github.com/pycontribs/pytest-molecule/blob/master/pytest_molecule/<strong>init</strong>.py#L53</a></p>
  
  <p>Mainly I want to conditionally add the "foo" mark so some of the discovered tests but I was not able to find any documentation on how to do it with classes based on <code>pytest.Item</code> .</p>