apt-get install -t experimental python3-pyqt5 python3-pyqt5.qtwebkit python3-pyqt5.qtquick python3-sip python3-dev

Reading package lists... Done
Building dependency tree       
Reading state information... Done
python3-dev is already the newest version.
python3-dev set to manually installed.
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 python3-pyqt5 : Depends: python3 (>= 3.5~) but 3.4.2-2 is to be installed
                 Depends: libpython3.5 (>= 3.5.0~b1) but it is not installable
                 Depends: libqt5core5a (>= 5.7.0) but 5.3.2+dfsg-4+deb8u2 is to be installed
                 Depends: libqt5dbus5 (>= 5.6.0~beta) but 5.3.2+dfsg-4+deb8u2 is to be installed
                 Depends: libqt5designer5 (>= 5.7.0) but 5.3.2-3 is to be installed
                 Depends: libqt5gui5 (>= 5.7.0) but 5.3.2+dfsg-4+deb8u2 is to be installed
                 Depends: libqt5help5 (>= 5.7.0) but 5.3.2-3 is to be installed
                 Depends: libqt5network5 (>= 5.7.0) but 5.3.2+dfsg-4+deb8u2 is to be installed
                 Depends: libqt5printsupport5 (>= 5.4.0) but 5.3.2+dfsg-4+deb8u2 is to be installed
                 Depends: libqt5test5 (>= 5.6.0~beta) but 5.3.2+dfsg-4+deb8u2 is to be installed
                 Depends: libqt5widgets5 (>= 5.7.0) but 5.3.2+dfsg-4+deb8u2 is to be installed
                 Depends: libstdc++6 (>= 5) but 4.9.2-10 is to be installed
                 Depends: qtbase-abi-5-7-1 but it is not installable
 python3-pyqt5.qtquick : Depends: python3 (>= 3.5~) but 3.4.2-2 is to be installed
                         Depends: libpython3.5 (>= 3.5.0~b1) but it is not installable
                         Depends: libqt5core5a (>= 5.7.0) but 5.3.2+dfsg-4+deb8u2 is to be installed
                         Depends: libqt5qml5 (>= 5.7.0) but 5.3.2-4 is to be installed
                         Depends: libqt5quick5 (>= 5.7.0) but 5.3.2-4 is to be installed
                         Depends: libqt5quickwidgets5 (>= 5.5.0) but 5.3.2-4 is to be installed
                         Depends: libstdc++6 (>= 5) but 4.9.2-10 is to be installed
                         Depends: qtdeclarative-abi-5-7-0 but it is not installable
 python3-pyqt5.qtwebkit : Depends: python3 (>= 3.5~) but 3.4.2-2 is to be installed
                          Depends: libqt5core5a (>= 5.7.0) but 5.3.2+dfsg-4+deb8u2 is to be installed
                          Depends: libqt5webkit5 (>= 5.6.0~rc) but 5.3.2+dfsg-4 is to be installed
                          Depends: libstdc++6 (>= 5) but 4.9.2-10 is to be installed
 python3-sip : Depends: python3 (>= 3.5~) but 3.4.2-2 is to be installed
 python3.5 : Depends: python3.5-minimal (= 3.5.3-1) but 3.5.3~rc1-1 is to be installed
             Depends: libpython3.5-stdlib (= 3.5.3-1) but 3.5.3~rc1-1 is to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).