new_contents: from brownant import Brownant, BrownAnt
  
  
  def test_deprecation(recwarn):
      app = BrownAnt()
      warning = recwarn.pop(DeprecationWarning)
  
      assert isinstance(app, Brownant)
      assert issubclass(warning.category, DeprecationWarning)
      assert "Brownant" in str(warning.message)
      assert "app.py" in warning.filename
      assert warning.lineno
  
subject: test the deprecation class.