You are confused as to what GPT-3 does.
I guess saying GPT-3 instead of AI or machine learning gives more marketing hype points. Like calling a landing page a "SAAS". (It's a joke, I hope you don't offended by it).
Sherlock Holmes received the following documents: [insert all 1500 documents here] then exclaimed, "A-ha, I have deduced who did it! It was