Connecting postgresql with sqlalchemy

You would need to pip install SQLAlchemy and pip install psycopg2.
An example of a SQLAlchemy connection string that uses psycopg2:

from sqlalchemy import create_engine
engine = create_engine('postgresql+psycopg2://user:password@hostname/database_name')

You could also connect to your database using the psycopg2 driver exclusively:

import psycopg2
conn_string = "host="localhost" dbname="my_database" user="postgres" password='secret'"
conn = psycopg2.connect(conn_string)

However, using the psycopg2 driver to connect does not take advantage of SQLAlchemy.