[web2py] can we use javascript in sqlform How?

[sagar]

I am using sql form
db.py
data=db.define_table('template_properties',
                    Field('temp_uid', 'string',default=uuid.uuid1(),
writable=False, readable=False),
                    Field('template_name', default=''),
                    Field('deadline','datetime'),
                    Field('type','string',
requires=IS_IN_SET(['onetime','daily','weekly','custom'])),
                    )


I am using sql form

def add():
         form=SQLFORM(db.template_properties)


I have to add extra textbox once user select custom  value for type
field...