gh-143200: fix UAFs in Element.__{set,get}item__ when the element is concurrently mutated
#101895
| Job | Run time |
|---|---|
| 32s | |
| 32s |
Element.__{set,get}item__ when the element is concurrently mutated
#101895
| Job | Run time |
|---|---|
| 32s | |
| 32s |