Как установить flask_sqlalchemy
$ pip install -U Flask-SQLAlchemy
Easy Emu
$ pip install -U Flask-SQLAlchemy
py -m pip install Flask-SQLAlchemy#If u want to add installl a specifc version of sqlachemy
pip install -U Flask-SQLAlchemy==verision
#for example:
pip install -U Flask-SQLAlchemy ==2.1