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First clone this repo by using following command
git clone https://github.com/Sanjeev-Thiyagarajan/fastapi-course.git
then
cd fastapi-course
Then install fastapp using all flag like
pip install fastapi[all]
Then go this repo folder in your local computer run follwoing command
uvicorn main:app --reload
Then you can use following link to use the API
http://127.0.0.1:8000/docs