"pg_back" is an invalid Debian package name ("_" not allowed)

[jmbourdaret]

"pg_back" is an invalid package name.

It does not comply with the Debian package naming rules : https://www.debian.org/doc/debian-policy/ch-controlfields.html#source

Package names (both source and binary, see Package) must consist only of lower case letters (a-z), digits (0-9), plus (+) and minus (-) signs, and periods (.).

Looks like debian does not allow _ (underscore) in package names.

Not much of an issue most of the time, but I stumbled upon this debsums tool which was reporting a warning about this:

$ sudo debsums -ce
debsums: invalid package name 'pg_back'

There might be others out there who might be real picky...