Comment # 1 on bug 1057934 from Martin Pluskal

(In reply to Giacomo Comes from comment #0)
> After a standard installation, I found this error in /var/log/zypp/history:
> 
> # 2017-09-07 15:43:23 python3-chardet-3.0.4-2.1.noarch.rpm installed ok
> # Additional rpm output:
> # /var/tmp/rpm-tmp.wMwH5i: line 2: update-alternatives: command not found
> # warning: %post(python3-chardet-3.0.4-2.1.noarch) scriptlet failed, exit
> status 127
> # 
> 2017-09-07
> 15:43:23|install|python3-chardet|3.0.4-2.1|noarch||openSUSE-20170904-
> 0|871c8546fa455d945d37149899ef47b6d8beed8d|
> 
> The problem is that python3-chardet is installed before update-alternatives
> and at that time the binaries update-alternatives used in the postinstall
> scriptlet, is not available yet.
> 
> A possible fix is to add this lines in python-chardet.spec:
> 
>  BuildRequires:  python-rpm-macros
> +Requires(post): update-alternatives

Yep, thats would be correct fix

Interestingly maintainer seems to be alexandre.rogoski@rgk4it.com but his
account is not available in bugzilla, thus issue cant be assigned to him