Currently dev-python/matplotlib have STRICT="mirror" with no visible reason. Please remove it.
commit 9dc17d867d8d41905eb2c887b92b5b038f5f0655 Author: Justin Lecher <jlec@gentoo.org> Date: Tue Nov 3 09:08:37 2015 +0100 dev-python/matplotlib: Drop obsolete mirror restriction Gentoo-Bug: https://bugs.gentoo.org/show_bug.cgi?id=564714 Package-Manager: portage-2.2.23 Signed-off-by: Justin Lecher <jlec@gentoo.org> https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=9dc17d867d8d41905eb2c887b92b5b038f5f0655