setup.py install does not honor --prefix

[Rhys Ulerich]

The source tarball's setup.py does not honor 'python setup.py install --prefix=$HOME' correctly. The initial installation fails with
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[267 rhys@gauss gnome-wallchanger-2.7]$ python setup.py install --prefix=$HOME
running install
running build
running build_scripts
creating build
creating build/scripts-2.5
copying random-wallpaper -> build/scripts-2.5
copying gnome-wallchanger-config -> build/scripts-2.5
running install_scripts
copying build/scripts-2.5/gnome-wallchanger-config -> /h2/rhys/bin
copying build/scripts-2.5/random-wallpaper -> /h2/rhys/bin
changing mode of /h2/rhys/bin/gnome-wallchanger-config to 755
changing mode of /h2/rhys/bin/random-wallpaper to 755
running install_data
creating /h2/rhys/share/wallpaper-changer
creating /h2/rhys/share/wallpaper-changer/glade
copying glade/wallchanger.glade -> /h2/rhys/share/wallpaper-changer/glade/
copying random-wallpaper.py -> /h2/rhys/share/wallpaper-changer/
copying gnome-wallchanger-config.py -> /h2/rhys/share/wallpaper-changer/
copying setup.py -> /h2/rhys/share/wallpaper-changer/
copying lib/config.py -> /h2/rhys/share/wallpaper-changer/
copying lib/lister.py -> /h2/rhys/share/wallpaper-changer/
copying wallchanger.png -> /h2/rhys/share/wallpaper-changer/
copying wallchanger.desktop -> /usr/share/applications/
error: /usr/share/applications/wallchanger.desktop: Permission denied
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Later, attempting to run $HOME/bin/gnome-wallchanger-config also dies
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[253 rhys@gauss bin]$ ./gnome-wallchanger-config
cd: 2: can't cd to /usr/share/wallpaper-changer/
/usr/bin/python: can't open file '/usr/share/wallpaper-changer/gnome-wallchanger-config.py': [Errno 2] No such file or directory
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It seems that both the install and installed helper "binary" fail to allow an installation prefix. This prevents the application from being used on a system where the user does not have root access.