At least dozen different file type use .pkg extension, so prt to pkg conversion may be searched because of many things. Not only are both common file extension, but also abbreviations, so some people might be searching for this even for completely different reasons.
In most cases .prt files are used for CAD 3D parts and thus this export is probably related to this area as well. Perhaps as some kind of package export, or similar.
The crucial part will be to determine the origin of the source .prt file, this will help in finding a tool that can be used to export or convert prt to pkg tremendously.
Updated: January 10, 2024