from sqlalchemy import *
from sqlalchemy.orm import declarative_base,sessionmaker

db_url='mysql+pymysql://root:123456@127.0.0.1:3306/student_manage_system?charset=utf8mb4'
engine = create_engine(db_url)

Base = declarative_base()
Session = sessionmaker(bind=engine, autoflush = False, autocommit = False)

def get_db():
    db = Session()
    try:
        yield db
    finally:
        db.close()