Bug#922243: mailman3-full : Depends: mailman3 but it is not going to be installed

[Pierre-Elliott Bécue]

Hi.

mailman3 is not part of stretch but stretch-backports.

Your sources.list has stretch-backports commented out.

Please,uncomment the backports lines, run an aptitude update and try again 
installing mailman3-full

Best regards. 
-- 
PEB from my phone.