You should make lookup.pm a module and "use" it. Here's an example:

#!/usr/bin/perl

use strict;
use warnings;
use Lookup;
use Data::Dumper;

print Dumper \%devel_table;
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And then the Lookup.pm module (I usually capitalize modules):

package Lookup;

use strict;
use warnings;
require Exporter;

our @EXPORT = qw(%devel_table);
our @ISA = qw(Exporter);

our %devel_table = ("Townhomes West" => "M",
              #lots more values in here, of course
             "Winding Creek Family" => "H",
             "Dayton Lane Gardens" => "H");

1;
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