#!/usr/bin/perl
use strict;
use warnings;

my %in_out = (
    foo => 'bar',
);

$in_out{foot}{bart} = sub {
    return "subsub";
};

my %test2 = (
    insub   => sub {
        my ($get2) = @_;
        my $resp = $get2->{foot}->bart();
        say $resp;
    },
);

$test2{insub}->(\%in_out);