Action which moves the selected files and files in selected folders
        to clipboard.

def move_to_clipboard(self, request, files_queryset, folders_queryset):
        """
        Action which moves the selected files and files in selected folders
        to clipboard.
        """

        if not self.has_change_permission(request):
            raise PermissionDenied

        if request.method != 'POST':
            return None

        clipboard = tools.get_user_clipboard(request.user)

        check_files_edit_permissions(request, files_queryset)
        check_folder_edit_permissions(request, folders_queryset)

        # TODO: Display a confirmation page if moving more than X files to
        # clipboard?

        # We define it like that so that we can modify it inside the
        # move_files function
        files_count = [0]

        def move_files(files):
            files_count[0] += tools.move_file_to_clipboard(files, clipboard)

        def move_folders(folders):
            for f in folders:
                move_files(f.files)
                move_folders(f.children.all())

        move_files(files_queryset)
        move_folders(folders_queryset)

        self.message_user(request, _("Successfully moved %(count)d files to "
                                     "clipboard.") % {"count": files_count[0]})

        return None