Why people don't switch to python 3?
<p>Python 3 has been released more than 3 years ago. Until now, most of the framework and coursework i have seen always based on python 2.6 (or 2.7)</p>

<p>Even for Google App Engine, they also use python 2.</p>

<p>Are there any drawback of python 3 that prevents people from upgrading?</p>
