Why mod_python is oop but mod_php is not ?
Example :We go to www.example.com/dir1/dir2
if you use mod_python apache opens www/dir1.py and calls dir2 method
but if you use php module apache opens www/dir1/dir2/index.php
I think you have some misconceptions about how HTTP works. Nothing in the http standard requires you to have a certain file as a resource. It is just the way how mod_php works, that for a given path, this path is translated to a php file on the disk of the server, which in turn is interpreted by the compiler.
The mod_python module on the other hand is much more generic, it allows you to map any resource to a call to some python object. It just happens that some configurations are available out of the box, to make it easier to start with. In most cases the dispatch of the url is managed by your framework, and how that works is up to the framework implementor.
Because of the generic nature of the mod_python module you are also able to access some apache features which are not available in the mod_php module, for instance you may write your own authentication handler, which my not only apply to your python webapp, but also to other apps in your apache as well.
mod_php vs mod_python