[web2py] Going through the book, I get, name 'form' is not defined

[Noel Kurian]

Hello guys,

Today, I was looking for a framework that would work with google app engine 
and I came across web2py.... It looked interesting so I thought let me give 
it a try... 

So, I'm going through the book/manual and when I try to do the example on 
page 83, it gives me following error:

<type 'exceptions.NameError'> name 'form' is not defined
Here's my controller/action code:
def first():
    form = SQLFORM.factory(Field('visitor_name', requires=IS_NOT_EMPTY()))
    if form.process().accepted:
        session.visitor_name = form.vars.visitor_name
        redirect(URL('second'))
    return dict()

I'm running python2.7.3rc2. Any help would be appriciated.

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