The only change I made to my code was to get it to run after upgrading. Here is My/Lib.pl:

use v5.16;
use utf8;
use warnings;

package My::Lib;
use Perl6::Export::Attrs;

sub foo :Export {
    return 5; 
}   

1;
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Here is my test code:

#!/usr/local/bin/perl

use strict;
use warnings;

use My::Lib qw{foo};

my $foo = foo ();
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The error returned is

My::Lib does not export: foo
use My::Lib failed at ./t.pl line 7.
BEGIN failed--compilation aborted at ./t.pl line 7.
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