How to dynamically replace contents of HTML tags with Python on Google App Engine with lxml?
Question: I am using Google app engine and python to build an application. I am
incredibly new to python as well as GAE. I have a index.html file with the
basic template for my site. However I would like to replace the contents of a
few tags depending on the URL. For example update the title tag for each
individual pages. From what I can tell the recommended way to do this is using
the lxml library.

And so... Tonight is my first time I have ever worked with lxml and I am
having a really hard time wrapping my head around it. I have been fooling
around with several permutations of the basic syntax and have not had much
success understanding how it works. I have looked for different tutorials and
the documentation is few and far between.

When I try the following code I get a 'lxml.etree._ElementTree' object has no
attribute 'find_class' error, however the documentation here:
<http://lxml.de/lxmlhtml.html#parsing-html> it sure looks like it should have
that class

Am I on the right path? Is this the most efficient/best way to replace the
content of html tags?

    
    
    import os
    import webapp2
    import lxml.html
    
    doc = lxml.html.parse('index.html')
    doc.find_class("title") == 'About Page'
    self.response.write(lxml.html.tostring(doc))
    


Answer: This is definitely not the way to that on Google App Engine. You should use
some kind of template framework like Jinja2 or Django to achieve your goal.

But before all that you will have to make sure that you completed the [Getting
Started
Tutorial](https://developers.google.com/appengine/docs/python/gettingstartedpython27/),
where you can see these things in action.

