[web2py] SQLFORM input attributes

[cjung89]

In the web2py book there is this function in the overview for the wiki
demo:

def search():
     "an ajax wiki search page"
     return dict(form=FORM(INPUT(_id='keyword',_name='keyword',
              _onkeyup="ajax('bg_find', ['keyword'], 'target');")),
              target_div=DIV(_id='target'))

I was wondering if there is a way to set the onkeyup attribute for a
field in a SQLFORM, since the with a SQLFORM the forms are generated
from the model.