问题确认 Search before asking

• 我已经查询历史issue(包括open与closed)，没有发现相似的bug。I have searched the open and closed issues and found no similar bug report.

Bug描述 Describe the Bug

python export.py --config configs/mscale_ocr_cityscapes_autolabel_mapillary.yml --save_dir ./output --input_shape 1 3 2048 1024
按照readme要求在制定位置下载了模型参数和预训练参数，使用以上命令导出预训练的模型网络时，出现以下报错
尝试了历史issue中提到的几种方法，例如通过源码安装开发版paddleseg，问题仍然存在
利用飞浆ai studio的notebook也同样存在此问题，和配置环境应该无关

报错内容
d:\deeplearning\paddleseg\paddleseg\cvlibs\manager.py:113: UserWarning: MscaleOCRNet exists already! It is now updated to <class 'models.mscale_ocrnet.MscaleOCRNet'> !!!
warnings.warn("{} exists already! It is now updated to {} !!!".
Traceback (most recent call last):
File "D:\DeepLearning\PaddleSeg\contrib\CityscapesSOTA\export.py", line 140, in
main(args)
File "D:\DeepLearning\PaddleSeg\contrib\CityscapesSOTA\export.py", line 84, in main
net = cfg.model
AttributeError: 'Config' object has no attribute 'model'

复现环境 Environment

paddlepaddle-gpu 2.4.2.post117
paddleseg 2.8.0 d:\deeplearning\paddleseg

Bug描述确认 Bug description confirmation

• 我确认已经提供了Bug复现步骤、代码改动说明、以及环境信息，确认问题是可以复现的。I confirm that the bug replication steps, code change instructions, and environment information have been provided, and the problem can be reproduced.

是否愿意提交PR？ Are you willing to submit a PR?

• 我愿意提交PR！I'd like to help by submitting a PR!