Cannot call Gio::File::new_for_path

[David Breeding <debmint49 gmail com>]

Trying to implement the following code:

my $cs = Gtk3::CssProvider->new();
$cs->load_from_file(Gio2::File::new_for_path("$ENV{HOME}/.config/poolstore/ps.css"));
my $context = $w_main->get_style_context();

Gtk3::StyleContext::add_provider_for_screen($context->get_screen(),
        $cs, 600);

However, I get error that Gio2::file_new_for_path does not exist.  I've tried using simply Gio (it appears from doc that it is now Gio2). Also tried other variations like GFile in place of Gio with no success.

perli11ndoc shows this function as existing (both in Gio and Gio2 namespace)

OS is Debian 10 but also tried on Arch with same result

I tried "use Gio" directive getting error.  Looked for files on either system with path ending in /Gio/File.pm and none existed,

Would like to get this to work.  I do have his program also implemented in PyGobject and this function works, so it doesn't appear to be a problem with GObject-Introspection itself.

Any help will be appreciated.