Sample project demo for python flask
APP_SETTINGS is a environment variable stored in bashrc / zshrc
export APP_SETTINGS=/Users/sazzad/.usrConfig/app.cfg
app.cfg contains
MONGO_HOST='192.168.0.1'
MONGO_PORT=27017
MONGO_DBNAME='dbname'
MONGO_USERNAME='db_username'
MONGO_PASSWORD='db_password'