运行数据集：assert args.dataset in recognized_datasets, 'is not supported,

train文件夹在E:\aidatatang_200zh_2\aidatatang_200zh\corpus，根目录就是E:\aidatatang_200zh_2吧？但是好像不太对劲，如图

Start by locating the `assert args.dataset in recognized_datasets` entry point and compare its expected dataset names and root-path handling with the reported `E:\aidatatang_200zh_2` and `train` paths. Reproduce the assertion with the shown layout; done means the expected path or supported dataset configuration is unambiguous and the dataset is accepted, or the issue clearly identifies what is unsupported.

Written by the indexing model from the issue text.