a=1
if a>0:
       print "hello world"
       print a

a=1
if a>-10:
       while a>-10:
              print "Hello World"
              a=a-1
       print "Hello World the last time"
else:
       print "Hello World only once"

print a

The IModel interface is documented in 
twisted.web.woven.interfaces. It describes the 
interfaces Models must implement in order to play 
well with the rest of the woven MVC framework. If you 
are inheriting from twisted.web.woven.model.Model, 
most of these interfaces will be implemented for you. 
The interfaces that we will be most interested in 
implementing are those that are designed to be 
overridden for customization, getData and setData.