Ubuntu – How to list the contents of a package

I try to fill or complement what @SeanBright leaved out:

Feature                              rpm                                   deb
----------------------------------------------------------------------------------
View all installed packages          rpm -qa                               dpkg -l, dpkg-query -Wf '${Package}\n'
View package info, installed package rpm -qi packagename (1)               apt-cache show packagename
View pre/post install shell scripts  rpm -q --scripts packagename          cat /var/lib/dpkg/info/packagename.{pre,post}{inst,rm}
View changelog for a package file    rpm -qp --changelog ./packagename.rpm dpkg-deb --fsys-tarfile packagename.deb | tar -O -xvf - ./usr/share/doc/packagename/changelog.gz | gunzip
Uninstall a package                  rpm -e packagename                    apt-get remove/purge packagename
Upgrade a package from a file        rpm -Uvh ./packagename.rpm            dpkg -i packagename.deb
Find which package owns a file       rpm -qif /some/file.foo               dpkg -S /dome/file.foo
List dependencies of a package       rpm -q --requires packagename         apt-cache depends package
List dependencies of a package file  rpm -qp --requires ./packagename.rpm  (shown in package's info)

At the end of /etc/bash.bashrc you'll find some commands which ultimately define the bash function command_not_found_handle. Then man bash tells us that this command is invoked when a non-existing command is typed in. On my machine, the handle invokes /usr/lib/command-not-found as a python script. This again leads into /usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py which seems to invoke apt-get or aptitute (search for the two in the file).