def build_instances(self, ctxt, **kwargs):
        """Build instances."""
        build_inst_kwargs = kwargs
        instances = build_inst_kwargs['instances']
        build_inst_kwargs['image'] = jsonutils.to_primitive(
                build_inst_kwargs['image'])

        version = '1.34'
        if self.client.can_send_version('1.34'):
            build_inst_kwargs.pop('legacy_bdm', None)
        else:
            bdm_p = objects_base.obj_to_primitive(
                    build_inst_kwargs['block_device_mapping'])
            build_inst_kwargs['block_device_mapping'] = bdm_p
            version = '1.32'
        if not self.client.can_send_version('1.32'):
            instances_p = [jsonutils.to_primitive(inst) for inst in instances]
            build_inst_kwargs['instances'] = instances_p
            version = '1.30'
        if not self.client.can_send_version('1.30'):
            if 'filter_properties' in build_inst_kwargs:
                filter_properties = build_inst_kwargs['filter_properties']
                flavor = filter_properties['instance_type']
                flavor_p = objects_base.obj_to_primitive(flavor)
                filter_properties['instance_type'] = flavor_p
            version = '1.8'
        cctxt = self.client.prepare(version=version)
        cctxt.cast(ctxt, 'build_instances',
                   build_inst_kwargs=build_inst_kwargs)
dataset/ETHPy150Open BU-NU-CLOUD-SP16/Trusted-Platform-Module-nova/nova/cells/rpcapi.py/CellsAPI.build_instances/original