Man pages matching name package::deprecationmanager in section 3pm:

Package::DeprecationManager.3pm.en	debian 10 / libpackage-deprecationmanager-perl
Package::DeprecationManager.3pm.en	debian 11 / libpackage-deprecationmanager-perl
Package::DeprecationManager.3pm.en	debian 12 / libpackage-deprecationmanager-perl