This gist has the JSON data for qtpygraph
's coverage badge.
It uses https://github.com/marketplace/actions/dynamic-badges to generate a JSON file that shields.io can render.
The image URL is: https://img.shields.io/endpoint?url=https://gist.githubusercontent.com/adam-grant-hendry/93a225b73dfa5ee041e6786dfbeff9ad/raw/coverage_badge.json