Error: Topformer is not in models registry

[nralka2007]

I am trying to use this with a custom dataset

lib/python3.7/site-packages/mmcv/utils/registry.py", line 62, in build_from_cfg
f'{obj_type} is not in the {registry.name} registry')
KeyError: 'Topformer is not in the models registry'

What could be the reason for this

[tranquan687]

i have a same issue when i try to run inference with pretrain