'Put up the login form'

def __call__(self, cookie=None, policy_url=None, logo_url=None, query='', **kwargs):

    if cookie:
        headers = [cookie]
    else:
        headers = []
    resp = Response(headers=headers)
    argv = {'login': '', 'password': '', 'action': 'verify', 'policy_url': policy_url, 'logo_url': logo_url, 'query': query}
    logger.info(('do_authentication    argv:    %s' % argv))
    mte = self.template_lookup.get_template(self.mako_template)
    resp.message = mte.render(**argv)
    return resp
