[web2py] doubt (needed urgently)

[qwer qwer]

why doesn't it work?     How to make it work?? Thanks 
Enter code here...{{form=FORM('Your comment:',INPUT(_comment='_comment',requires
=IS_NOT_EMPTY()),
          INPUT(_type='submit'))}}
{{        def ded():  if form.accepts(request,session): response.flash = 
'Your information has been sent successfully'}}

{{=form}}
{{ded()}}

:) 

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