Write me a script to convert a p12 (pkcs12) file to a json file

I need a script that can be executed in Linux (Ubuntu 18.0.4) that will locate a Private Key file in p12 format in root/constellation/[filename].p12 and convert it to a Private Key in json format file at root/constellation[filename].json

I can provide sample p.12 and their matching json files to enable you to identify the fields that need to be captured and included.

Thank you.