[bug#68937] [PATCH 2/3] gnu: brltty: Fix python package install.

[Dariqq <dariqq@posteo.net>]

The python package is not being installed properly due to install directory not
being on PYTHONPATH.

* gnu/packages/accessibility.scm (brltty)[phases]: Add add-install-to-pythonpath-phase.
[modules, imported-modules]: Add (guix build python-build-system).

Change-Id: Ia9a24f872d82c3e582413eb1d9fc4df3e0979916
---
 gnu/packages/accessibility.scm | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/gnu/packages/accessibility.scm b/gnu/packages/accessibility.scm
index 0b5fb79f13..1b5fd6db50 100644
--- a/gnu/packages/accessibility.scm
+++ b/gnu/packages/accessibility.scm
@@ -129,6 +129,11 @@ (define-public brltty
          "PYTHON_ROOT=/"
          (string-append "TCL_DIR=" #$output "/lib")
          "INSTALL_WRITABLE_DIRECTORY=no-thanks")
+      #:imported-modules `((guix build python-build-system)
+                           ,@%glib-or-gtk-build-system-modules)
+      #:modules '((guix build utils)
+                  (guix build glib-or-gtk-build-system)
+                  ((guix build python-build-system) #:prefix python:))
       #:phases
       #~(modify-phases %standard-phases
           (add-after 'unpack 'fix-errors
@@ -142,7 +147,10 @@ (define-public brltty
                  (string-append "extra_link_args = ['-Wl,-rpath="
                                 #$output
                                 "/lib'], "
-                                "extra_compile_args = "))))))))
+                                "extra_compile_args = ")))))
+          (add-before 'install 'set-pythonpath
+            (assoc-ref python:%standard-phases
+                       'add-install-to-pythonpath)))))
     (native-inputs
      (list clisp
            python-cython
-- 
2.41.0