How can I use open_http in lxml.html.submit_form to alternate opener?

I don't know how to fix the last line of code.

from lxml.html import parse, submit_form
fundurl = 'http://www.aia.com.hk/en/investment-information/fund_search_content_new.jsp?fund=c04&tier=sp_br&todate=&date=&name='
page = parse(fundurl).getroot()
form = page.forms[0]
form.fields['date'] = '08/09/2004'
form.fields['todate'] = '3m'

#### THE FOLLOWING CODE IS INCORRECT ####
result = parse(submit_form(form, {'submit':'Search'}, open_http('GET', 'http://www.aia.com.hk/en/investment-information/fund_search_content_new.jsp?fund=c04&tier=sp_br&todate=&date=&name=', {'date':'08/19/2004','todate':'3m'})))