Hm, a comment would be ok. Or how about this:
```
status_tag = 'ENOMULTI'    # It is an error to submit multiple times for the same item
# other initializations go here
# elide lines 52-54...
if not prev_sub:
```
Then we remove a dead line and eliminate a branch of the if. It increases the code density, but arguably may lower the complexity over all - which would be a win, neh?