<!ENTITY keyring-package "<package>ubuntu-keyring</package>">
<!ENTITY keyring-filename "<filename>/usr/share/keyrings/ubuntu-archive-keyring.gpg</filename>">
<!ENTITY keyring-removed-filename "<filename>/usr/share/keyrings/ubuntu-archive-removed-keys.gpg</filename>">
+<!ENTITY keyring-master-filename "/usr/share/keyrings/ubuntu-master-keyring.gpg">
+<!ENTITY keyring-uri "http://archive.ubuntu.com/ubuntu/project/ubuntu-archive-keyring.gpg">