Try this Values, If the second.class obj
has partner
than one2many
is created.
obj = self.browse(cr, uid, ids)[0]
if obj.partner_id:
vals{
'partner_id': obj.partner_id.id,
'res_ids': [(0,0, {
'partner_id': obj.partner_id.id, #give id of partner
'first_id': obj.first_id.id #give id of first
})]
}
self.pool.get('first.class').create(cr, uid, vals)