A simple, lightweight shell script to use OpenAI's chatGPT and DALL-E
from the terminal without installing python or node.js. The script uses
the official ChatGPT model `gpt-3.5-turbo` with the OpenAI API endpoint
`/chat/completions`. You can also use the new `gpt-4` model, if you
have access.

The script supports the use of all other OpenAI models with the
`completions` endpoint and the `images/generations` endpoint for
generating images.