gh-142495: make defaultdict keep existed value when racing with __missing__
#226199
| Job | Run time |
|---|---|
| 5s | |
| 6s | |
| 11s |
defaultdict keep existed value when racing with __missing__
#226199
| Job | Run time |
|---|---|
| 5s | |
| 6s | |
| 11s |