human
Solve the following python programming problem given the following code:
@ pytest.yield_fixture 
def db_session(app_config) : 
    engine = app_config.registry ['sqlalchemy.engine'] 
    conn = engine.connect () 
    trans = conn.begin () 
    session = Session (bind = restart_savepoint) 
    session.begin_nested () 
    @ event.listens_for (session, 'after_transaction_end') 
    def restart_savepoint(session, transaction) : 
        if (transaction.nested and (not transaction._parent.nested)) : 
            session.begin_nested () 
try : 
        (yield session) 
finally : 
        session.close () 
        Session.remove () 
        trans.rollback () 
        conn.close () 
        engine.dispose () 

    
    

    Fix the buggy line: session = Session (bind = restart_savepoint)
assistant
#Here is Python code to fix the buggy line: session = Session (bind = restart_savepoint)
.

session = Session (bind = conn)