装配时如何导入添加事例

tari

tag_t parent_part;
     parent_part=UF_open_part();
     const char child_part[]="E:\\my_first_UG\\application\\bb.prt";
         const char *refset_name=NULL;
     const char instance_name[]="bb";
     double origin[3]={0,0,0};
     double csys_matrix[9]={1,0,0,0,1,0,0,0,1};
     int layer=0;
     tag_t instance;    
     UF_PART_load_status_t error_status;
     UF_ASSEM_add_part_to_assembly(parent_part,child_part,refset_name,instance_name,
       origin,csys_matrix,layer,[$instance,&error_status)] 问题出在哪里，参数设置？bb.prt部件一直没添加进去，郁闷中！