title: Q object with string in django
body: <p>I am filtering participants with a Q object:</p>
  
  <pre><code>q_databases.append(Q(sign_in_link="n"))
  </code></pre>
  
  <p>This is converted (with the <code>query</code> attribute) in sql with:</p>
  
  <pre><code>`participants_participant`.`sign_in_link` = n
  </code></pre>
  
  <p>There is no quote around the string <code>n</code> so I get an error when I copy paste the sql script in an sql console.
  What is wrong?</p>