The following packages have unmet dependencies:
unity8-desktop-session : Depends: qtubuntu-desktop but it is not going to be installed
Depends: unity8 but it is not going to be installed
Depends: url-dispatcher but it is not going to be installed
Recommends: indicator-transfer but it is not installable
Recommends: qtubuntu-print but it is not installable
Recommends: ubuntu-terminal-app but it is not going to be installed
Recommends: unity-scope-mediascanner2 but it is not installable
Recommends: webbrowser-app but it is not installable
E: Unable to correct problems, you have held broken packages.