open-mmlab/mmpose ? reverse-engineered prompt

Build me an open source pose estimation toolkit in Python that can detect human body keypoints, hands, faces, whole body keypoints, and even animals from images and video.

I want it to include ready to run demos, training and testing scripts, a clean way to add new models or datasets, and good documentation so people can get started quickly. It should support both faster real time models and more accurate ones, and make it easy to compare them on common pose datasets. Please include a model zoo with pretrained checkpoints, example configs, and simple command line tools for inference and evaluation.

Use PyTorch, keep it well organized, and make sure it feels like a serious research codebase that can also be used in real projects. If you need to check current best practices or docs online while building it, go ahead and do that.