python3-xlib: updated python syntax

python3-xlib/.signature

@@ -1,5 +1,5 @@
 untrusted comment: verify with /etc/ports/contrib.pub
-RWSagIOpLGJF39++cYBe9NIU2IV4FxAwAy+BXZc7qSqEPNWfNDBzuTHjnbqKWaKaqJh8aJjX4dJBePEFT1tC4s3eZfwIqn7YqQk=
-SHA256 (Pkgfile) = 108ceb64a3f0c4d200ee37a4e449f05738bf9760c630a6598ee0aae2e4aaafb2
+RWSagIOpLGJF30vKzP26Nsb/8An6l01in9veEcNwKv83IMALEieqkntMcpgSdM+yWt65Gp9V/k2iEeFxTKbf0QbxmLGKpcRgMwE=
+SHA256 (Pkgfile) = 84fabc7cacbc21a33a4d12d35a82c54d549183817dce8c0a042b1e15e886e333
 SHA256 (.footprint) = 41e6e1fee6595b62b8d30707319e74343666e9ded07963447156260b68452434
 SHA256 (python-xlib-0.28.tar.bz2) = 9b101976ade381d10f1c81c66ba198d85be104f624a9d7ab4b6f3bbcb0efd01b

python3-xlib/Pkgfile

@@ -10,8 +10,10 @@ source=(https://github.com/python-xlib/python-xlib/releases/download/$version/py
 
 build() {
   cd python-xlib-$version
-  python3 setup.py build
-  python3 setup.py install --root=$PKG --optimize=1 --skip-build
+  /usr/bin/python3 setup.py build
+  /usr/bin/python3 setup.py install --root=$PKG \
+    --optimize=1 \
+    --skip-build
   find $PKG \(\
     -iname '*pkg-info*' -o \
     -iname '*sources*' -o \