AttributeError: 'NoneType' object has no attribute '_instantiate_plugins' (Cannot import create_engine)

Question

import os

from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session, sessionmaker

engine=create_engine(os.getenv(\"DATABASE_URL\"))
db = scoped_se         


        

Answer 1

instead of

   engine=create_engine(os.getenv("DATABASE_URL"))
   db = scoped_session(sessionmaker(bind=engine))

type this with your url:

   engine = create_engine("postgresql://scott:tiger@localhost/mydatabase")
   db = scoped_session(sessionmaker(bind=engine))

Answer 2

just use this as url "postgresql://username:password@host:port/database" directly pass these values inside your create_engine("postgresql://username:password@host:port/database")

I was having the same problem now its gone.That worked for me. Only thing important to mention is that I got a different error altogether after creating the new user and database and moving the tables. The error was '

'' ModuleNotFoundError: No module named 'psycopg2' '''

and the solution was running: pip3 install psycopg2-binary

PS: URL details with you details.

Answer 3

It looks like os.getenv("DATABASE_URL") is returning None. Calling create_engine(None) give you this error. Is DATABASE_URL defined in your environment variable ?