In Domain how to call default method:-

    def _get_lotproduct(self, cr, uid, context=None):
        lot_obj = self.pool.get('stock.production.lot')
        lotids = lot_obj.search(cr, uid, [])
        product_id = []
        for val in lot_obj.browse(cr, uid, lotids):
            product_id.append(val.product_id.id)
        return product_id[0]


 'product_id': fields.many2one('product.product', 'Product',  domain="[('product_id','=',_get_lotproduct)]"),

    _defaults = {
           'product_id'   : _get_lotproduct
    }

domain="[('product_id','=',_get_lotproduct)]" Is it possible to call default method in domain?