title: adding together 2 queries in SQLAlchemy?
body: <p>still pretty newish to sqlalchemy/sql as a whole, and im trying to solve a certain issue. i have 2 queries, one returning a list of messages sent by the current user, and another returning a list of messages received from another user:</p>
  <pre><code>messages_from = u.messages_received.filter_by(author_id=user_id).all()
  messages_to = u.messages_sent.filter_by(recipient_id=user_id).all()
  </code></pre>
  <p>my goal is to add together these 2 queries so that they return something like this:</p>
  <pre><code>user1 | this is the message content | &lt;timestamp&gt;
  user2 | this is another message     | &lt;timestamp&gt;
  user1 | this yet another messsage   | &lt;timestamp&gt;
  </code></pre>
  <p>im not sure what to use to achieve this. would i use a join? or something else? any help would be really appreciated! &lt;3</p>