What does bare strings in the body of a class definition mean?
<p>Here is a snippet of code from <code>django.core.exceptions</code>:</p>

<pre><code>class MiddlewareNotUsed(Exception):
    "This middleware is not used in this server configuration"
    pass
</code></pre>

<p>Is the bare string in the body of the class a mere literal for documentation ? Or does it perform some magic ?</p>
