focal_loss = lambda x,y: focal_loss_lgb(x, y, alpha=0.25, gamma=1.)
focal_loss_eval = lambda x,y: focal_loss_lgb_eval_error(x, y, alpha=0.25, gamma=1.)
model = lgb.train(best, self.lgtrain, fobj=focal_loss, feval=focal_loss_eval)