add coverage

README.md

@@ -11,6 +11,7 @@ _Structured extraction in Python, powered by OpenAI's function calling api, desi
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 Dive into the world of Python-based structured extraction, empowered by OpenAI's cutting-edge function calling API. Instructor stands out for its simplicity, transparency, and user-centric design. Whether you're a seasoned developer or just starting out, you'll find Instructor's approach intuitive and its results insightful.