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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def session(self):
 """ Creates a context with an open SQLAlchemy session. """

        engine = self.engine
        connection = engine.connect()
        db_session = scoped_session(
            sessionmaker(autocommit=False, autoflush=True, bind=engine))
        yield db_session
        db_session.close()
        connection.close()