def create_mirror(self, resource_name, target_name, mirror_type,
                      slave_resource_name, rpo=None, remote_rpo=None,
                      schedule=None, remote_schedule=None,
                      activate_mirror='no'):
        '''creates a mirror and returns a mirror object.
           target name must be a valid target from target_list,
           mirror type must be 'sync' or 'async',
           slave_resource_name would be the slave_cg name'''

        return self._create_mirror('cg', resource_name, target_name,
                                   mirror_type, slave_resource_name, rpo=rpo,
                                   remote_rpo=remote_rpo, schedule=schedule,
                                   remote_schedule=remote_schedule,
                                   activate_mirror=activate_mirror)
creates a mirror and returns a mirror object.
           target name must be a valid target from target_list,
           mirror type must be 'sync' or 'async',
           slave_resource_name would be the slave_cg name