Cannot resolve necessary USE flag changes

[cybass 1]

First of all I would like to mention that it has been only 4 days since I switched to funtoo from arch. I am enjoying it a lot. However understanding portage is being challenging. What I have encountered today is after updating my system I tried to install a thunar and emerge complained about a necessary change.

# > emerge -av xfce-base/thunar

These are the packages that would be merged, in order:

Calculating dependencies... done!

The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by dev-python/subunit-1.2.0-r1::python-modules-kit
# required by net-fs/samba-4.11.0::core-server-kit
# required by gnome-base/gnome-control-center-3.34.5::gnome-kit
# required by net-libs/gnome-online-accounts-3.34.1::gnome-kit[gnome]
# required by gnome-base/gvfs-1.42.2::gnome-kit[google]
# required by sci-geosciences/geocode-glib-3.26.2::gnome-kit
# required by dev-libs/libgweather-3.34.0::gnome-kit
# required by gnome-base/gnome-settings-daemon-3.34.1::gnome-kit
# required by gnome-base/gnome-session-3.34.2::gnome-kit
>=dev-python/testtools-2.3.0 python_targets_python2_7

Would you like to add these changes to your config files? [Yes/No] 

I said Yes Then

Autounmask changes successfully written.

 * IMPORTANT: config file '/etc/portage/package.use' needs updating.
 * See the CONFIGURATION FILES and CONFIGURATION FILES UPDATE TOOLS
 * sections of the emerge man page to learn how to update config files.

 * In order to avoid wasting time, backtracking has terminated early
 * due to the above autounmask change(s). The --autounmask-backtrack=y
 * option can be used to force further backtracking, but there is no
 * guarantee that it will produce a solution.

emerge: there are no ebuilds built with USE flags to satisfy "dev-python/pyrsistent[python_targets_python3_7(-)?,python_targets_python2_7(-)?,-python_single_target_python3_7(-),-python_single_target_python2_7(-)]".
!!! One of the following packages is required to complete your request:
- dev-python/testtools-2.3.0::python-modules-kit (Change USE: -python_targets_python2_7)
(dependency required by "dev-python/testtools-2.3.0::python-modules-kit" [ebuild])
(dependency required by "dev-python/subunit-1.2.0-r1::python-modules-kit" [ebuild])
(dependency required by "net-fs/samba-4.11.0::core-server-kit" [ebuild])
(dependency required by "gnome-base/gnome-control-center-3.34.5::gnome-kit" [ebuild])
(dependency required by "net-libs/gnome-online-accounts-3.34.1::gnome-kit[gnome]" [ebuild])
(dependency required by "gnome-base/gvfs-1.42.2::gnome-kit[google]" [ebuild])
(dependency required by "sci-geosciences/geocode-glib-3.26.2::gnome-kit" [ebuild])
(dependency required by "dev-libs/libgweather-3.34.0::gnome-kit" [ebuild])
(dependency required by "gnome-base/gnome-settings-daemon-3.34.1::gnome-kit" [ebuild])
(dependency required by "gnome-base/gnome-session-3.34.2::gnome-kit" [ebuild])

Then I run dispatch-conf to update /etc/portage/package.use and pressed u. Then when I rerun the installation

# emerge -av xfce-base/thunar

These are the packages that would be merged, in order:

Calculating dependencies... done!

The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by dev-python/subunit-1.2.0-r1::python-modules-kit
# required by net-fs/samba-4.11.0::core-server-kit
# required by gnome-base/gnome-control-center-3.34.5::gnome-kit
# required by net-libs/gnome-online-accounts-3.34.1::gnome-kit[gnome]
# required by gnome-base/gvfs-1.42.2::gnome-kit[google]
# required by sci-geosciences/geocode-glib-3.26.2::gnome-kit
# required by dev-libs/libgweather-3.34.0::gnome-kit
# required by gnome-base/gnome-settings-daemon-3.34.1::gnome-kit
# required by gnome-base/gnome-session-3.34.2::gnome-kit
>=dev-python/testtools-2.3.0 -python_targets_python2_7

Would you like to add these changes to your config files? [Yes/No] 

I repeat the process again and again but it doesn't help. So I can't install a lot of things, I tried to install testtools with -python_targets_python2_7 use flag and it still doesn't help.

I have been stuck with this for the entire day.

[nrc 51]

Run `ego sync` and then do a full update `emerge -auvDN @world` and try again.   2.4.0 is the current dev-python/testtools and it doesn't list a python_targets_python2_7 USE flag.

[cybass 1]

On 4/29/2020 at 10:07 AM, nrc said:

Run `ego sync` and then do a full update `emerge -auvDN @world` and try again.   2.4.0 is the current dev-python/testtools and it doesn't list a python_targets_python2_7 USE flag.

Thanks very much it has been resolved .