import os

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

engine = create_engine("postgresql://postgres:114920@localhost/Databases")
db = scoped_session(sessionmaker(bind=engine))

def main():
    Railway = db.execute("SELECT origin, destination, duration FROM Railway").fetchall()
    for railway in Railway:
        print(f"{railway.origin} to {railway.destination}, {railway.duration} minutes")

if __name__ == "__main__":
    main()

并得到了这个错误（如果可能的话，请分享代码，我被困在这个敌人很长一段时间）

C：\Web开发\Lecture 02