[Twisted-web] Nested templates?

[Alberto Trujillo]

There is any way to use nested templates without mix the python code 
with the html code.
I know, that I could solve this problem using Stan, or just writing html 
code inside the python file and after display what I want.
But that are exactly the option that I can't use. I have to nest the 
template keeping the html code and the python code in different file.
If some body can give a example, a tutorial, a address, o something that 
can help me, I'll be very pleasant.

Thank you very much