我有一个df： production_unit_id | defective_item | defective_item_count | items_produced_count | items_discarded_count
P108 |岩石| 46 | 1 | 315
P108 |剪刀| 47 | 3 | 309
P108 |岩石| 27 | 6 | 315
P085 |剪刀| 50 | 8 | 194
P774 |剪刀| 23 | 146 | 21
P774 |剪刀| 5 | 146 | 21
我希望输出为： production_unit_id | defective_item | defective_item_count | items_produced_count | items_discarded_count
P108 |岩石| 73 | 7 | 630
P108 |剪刀| 47 | 3 | 309
P085 |剪刀| 50 | 8 | 194
P774 |剪刀| 28 | 292 | 42
“defect_item”＆＃39;列应该分组并且＆＃39; defective_item_count＆＃39;应该添加相应的“defect_item＆＃39;
请帮忙。提前谢谢。