feat: support __getitem__ with slices for columns
#1081
| Job | Run time |
|---|---|
| 1m 59s | |
| 1m 50s | |
| 3m 49s |
__getitem__ with slices for columns
#1081
| Job | Run time |
|---|---|
| 1m 59s | |
| 1m 50s | |
| 3m 49s |