I know this is an old question but to anyone still looking for a solution if you're on windows at least.
users/AppData/roaming/Python/Python37/site-packages."uvicorn" and "uvicorn-X.XX.Xdist-info" folders, then go
to users/AppData/roaming/Python/Python37/Scripts and copy the
"uvicorn.exe"."C:\Program Files (x86)\Microsoft Visual Studio\Shared\Python37_64\Scripts"."uvicorn main:app --reload".And it should work now.
Me I've just copied folders:
to my default python folder: C:\Program Files\Python38\Scripts, and I added the link to the .exe file to the environment variables path. It worked!
Try do the following
python3 -m uvicorn main:app