I can't see how this would work. I tried to create some mock code:

use strict;

{
    package MyObj;

    sub new {
        my %obj; bless( \%obj, $_[0] ); return( \%obj );
    }

    sub items {
        my @things = ( 'key1' => 'v1', key2' => 'v2', );
        return( @things );
    }
}

my $myobj = MyObj->new();
print( "$_\n" ) foreach ( sort keys( $myobj->items() ) );
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but kept getting this error:

Type of arg 1 to keys must be hash
(not subroutine entry) at /tmp/deleteme.pl
line 25, near ") ) "
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