title: How to use SQLAlchemy in MVC designed applications?
body: <p>I know there is no absolute solution for my question. I just want to
  hear your suggestions and how you do this in your practice.</p>
  
  <p>In which layer of the MVC-pattern are all the SQLAlchemy objects
  located?</p>
  
  <p>How do you realize this?</p>