RCV1 dataset with 137 labels

[ayushbits]

Dear Authors @penghts ,

In the paper you mentioned that

There are 103 categories including all classes except for root in the hierarchy. According to [13–15], we also consider the 137 categories by adding some virtual classes.

Can you provide a snippet of the code that created 137 categories by introduction of dummy nodes and assignment of labels as mentioned in the footnote ?