title: AttributeError: 'NoneType' object has no attribute '_instantiate_plugins' (Cannot import create_engine)
body: <pre><code>import os
  
  from sqlalchemy import create_engine
  from sqlalchemy.orm import scoped_session, sessionmaker
  
  engine=create_engine(os.getenv("DATABASE_URL"))
  db = scoped_session(sessionmaker(bind=engine))
  
  def main():
      flights = db.execute("SELECT origin, destination, duration FROM flights").fetchall()
      for flight in flights:
          print(f"{flight.origin} to {flight.destination}, {flight.duration} minutes.")
  
  if __name__ == "__main__":
      main()
  </code></pre>
  
  <p>Traceback (most recent call last):
    File "list.py", line 6, in 
      engine=create_engine(os.getenv("DATABASE_URL"))
    File "C:\Users\Aakash\AppData\Local\Programs\Python\Python38-32\lib\site-packages\sqlalchemy\engine__init__.py",
  line 479, in create_engine
      return strategy.create(*args, **kwargs)
    File "C:\Users\Aakash\AppData\Local\Programs\Python\Python38-32\lib\site-packages\sqlalchemy\engine\strategies.py", line 56, in create
      plugins = u._instantiate_plugins(kwargs)
  AttributeError: 'NoneType' object has no attribute '_instantiate_plugins'</p>
  
  <p>And if change my code to: </p>
  
  <p><a href="https://i.stack.imgur.com/vTF6W.jpg" rel="nofollow noreferrer">The Problem and the traceback is in the picture.</a></p>