How to get the url of a page in OpenERP?

User is using OpenERP. I have a button on one web page. The button‘s action function is action_go() (code provided). When I click on a button, the code opens a new web page in a new tab in browser. Now, I want, in the button action handler function, action_go(), to read current IP address so I can make the new url to launch it with the button (code for that url provided)

Here is the code that uses url:

class mrp_bom_line(osv.osv):
    _inherit = ‘mrp.bom.line‘

    def action_go(self, cr, uid, ids, context=None):
        bom_obj = self.pool.get(‘mrp.bom‘)
                ip_address = ‘127.0.0.1:8069‘
        url = ‘http://‘ + ip_address + ‘/web#id=%s&view_type=form&model=mrp.bom&menu_id=448&action=565‘
        for bom_line in self.browse(cr, uid, ids, context=context):
            if bom_line.product_id.default_code > ‘300‘:
                bom_ids = bom_obj.search(cr, uid, [(‘product_id‘, ‘=‘, bom_line.product_id.id)], context=context)
                if bom_ids:
                                        return {‘type‘: ‘ir.actions.act_url‘,
                        ‘res_model‘: ‘ir.actions.act_url‘,
                        # ‘url‘:‘http://127.0.0.1:8069/web#id=%s&view_type=form&model=mrp.bom&action=452‘ % bom_ids[0] ,
                                                ‘url‘:url % bom_ids[0] ,
                        ‘nodestroy‘: True,
                        ‘target‘: ‘new_tab‘}

        return True