CKAN Ext ckanext-ytp-comments

While I try to install ckanext-ytp-comments on my CKAN installation on Linux, I followed steps mentioned in github GitHub - vrk-kpa/ckanext-ytp-comments: CKAN extension for adding comments to datasets

After that while I click on a Dataset, it throws error "Server Error ‘An internal server error occurred’ "
I’m not sure what additional steps might be required for this installation.

My requirement is to allow users put comments against Datasets.