Pipeline.from_pretrained(model_id)

components = stable_diffusion_txt2img.components

# weights are not reloaded into RAM
stable_diffusion_img2img = StableDiffusionImg2ImgPipeline(**components)
Note how the above code snippet makes use of DiffusionPipeline.components.

How does loading work?
	
As a class method, DiffusionPipeline.from_pretrained() is responsible for two things:
Download the latest version of the folder structure required to run