Unable to import InternalData to get Internal Data methods

Team,

We are trying to get Total.No.of.rows from Internal Data Source, where as unable to import the package.
https://api-docs.katalon.com/studio/v4.6.0.2/api/com/kms/katalon/core/testdata/InternalData.html

Does this requires any jar to be updated to the project?

In above statement unable to get InternalData methods

Any help would be appreciated.

Thanks