<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def getReadSession(self):
        ''' return scopted session '''
        if self.ReadSession is None:
            self.ReadSession=scoped_session(sessionmaker(bind=self.engine))

        return self.ReadSession