Get GPT-3 completion on google sheet using App script

1. Open a new Google Sheet file
2. Extension > Appscript
3. On Project Settings, put OPENAI_API_KEY under Script Properties
4. On Editor, copy paste code on script.js
5. Edit preface and prompt as needed
6. Select gpt3 as function to run and click Run

There are two ways:

1. Use it as a custom function, e.g. gpt3(A2) to use A2 as input prompt
2. Block range, click menu GPT3 > Fill. This will use left most column as input and right most column as output.