# init cache object at the begining of the program
my $CACHE = new Cache::FileCache( );

.....
.....

#### Cut, subroutine from module

  foreach my $tid (@completed){
    $results{$tid} = $CACHE->get($tid);

    unless(defined $results{$tid}) {
      $results{$tid} = $self->Complex_Crap($tid);
      # data will expire in cache in 10 minutes
      $CACHE->set($tid => $results{$tid}, "10 minutes");
    }

  }

  $self->Results(\%results);
  
  return($self);

}