how to consult the base class of a class
<p>Recently i am learning something about unicode in python2.7, and i want to know something about the base class of str, unicode, basestring, etc. and the relations of them, but i can't find a proper way to look up the base class of them expect read the source code.</p>

<p>e.g.</p>

<pre><code>class child(A):
    pass
</code></pre>

<p>How can i know the base class of child using functions?
The only way is reading the source code?</p>
