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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 revoke_session(self, sid='', token=''):
 """ Mark session as revoked but also explicitly revoke all issued tokens :param token: any token connected to the session :param sid: Session identifier """

        if not sid:
            if token:
                sid = self.handler.sid(token)
            else:
                raise ValueError('Need one of "sid" or "token"')

        for typ in ['access_token', 'refresh_token', 'code']:
            try:
                self.revoke_token(self[sid][typ], typ)
            except KeyError:  # If no such token has been issued
                pass

        self.update(sid, revoked=True)