Bug#987835: unblock: python2.7/2.7.18-7

[Matthias Klose]

Package: release.debian.org
Severity: normal
User: release.debian....@packages.debian.org
Usertags: unblock

Please unblock package python2.7. No code changes, just adding a breaks for
upgrades, see #987661 for the issue and the diff for the fix.