Description:
Upon calling dstat, it offers the option to choose the refresh frequency (delay, as CLI argument).
The latest dstat-0.7.4 (upstream release 2019-05-22) dies with an error as soon as invoked with this (very common) option:


$ dstat 10
You did not select any stats, using -cdngy by default.
Traceback (most recent call last):
File "./dstat", line 2825, in <module>
main()
File "./dstat", line 2684, in main
scheduler.run()
File "/usr/lib/python3.7/sched.py", line 151, in run
action(*argument, **kwargs)
File "./dstat", line 2729, in perform
oldcols = cols
NameError: name 'cols' is not defined


This makes using dstat a pain.
Workraround: Downgradde to dstat-0.7.3 and add to IgnorePkg


This is in fact an upstream bug. But since the project recently has orphaned/archived on Github ( https://github.com/dagwieers/dstat/issues/170 ), we won't get help from there.



Additional info:
* package version: dstat-0.7.4-3 (most probably all dstat-0.7.4-*)


Steps to reproduce:
dstat 10