By Katherine Crowson (https://github.com/crowsonkb, https://twitter.com/RiversHaveWings). It uses OpenAI's 256x256 unconditional ImageNet diffusion model (https://github.com/openai/guided-diffusion) together with CLIP (https://github.com/openai/CLIP) to connect text prompts with images.
Original notebook by https://twitter.com/rivershavewings/status/1419674445044539400?lang=en
Fork by sadnow (on GitHub)