changed class index in custom coco dataset

[ymb943]

DFINE-N was pretrained with COCO2017

1: person
2: bicycle
3: car
4: motorcycle
...

I want to do fine-tuninig with custom coco data.
that custom coco data has partial coco classes, for example,

1: person
4: motorcycle
...

But in my fine-tuining test, DFINE-N requires continuous class index (starting from 0) like

0: person
1: motorcycle
...

So, if I use this dataset (0: person, 1: motorcycle, ...) for fine-tuning DFINE-N, there is class index mismatch.
How to resolve this class index mismatch?