title: Can't query from django where field name has double underscore
body: <p>Can't query from django where field name has double underscore.
  This is because in the django query language <code>__</code> has its own meaning</p>
  
  <p>so how can I query a field whose actual name is <code>"my__fyeild__name"</code> ?</p>
  
  <pre><code>template.fields.filter(my__fyeild__name="aaa")
  </code></pre>
  
  <p>In the database the column has a name with two underscores <code>__</code>, and I am not allowed to rename that column.</p>