title: translate from SQL to SQLAlchemy
body: <p>i have the following sql script.</p>
  
  <pre><code>SELECT *
  FROM movies
  LEFT JOIN possession
  ON movies.id = possession.movie_id
  AND possession.master_id = ?
  WHERE possession.id is NULL
  ORDER BY movies.id DESC
  </code></pre>
  
  <p>and need help to illustrate in sqlalchemy.
  Please can someone help me?</p>
  
  <p>The following doesn't work:</p>
  
  <pre><code>movies = movie.Movie.query.join(possession.Possession, movie.Movie.id == possession.Possession.movie_id)\
              .filter(possession.Possession.master_id == session.get('userId'))\
              .filter(not_(possession.Possession.id)).order_by(movie.Movie.id.desc()).all()
  </code></pre>
  
  <p>Thank you very much!</p>
  
  <p>Cheers</p>