my $sth_insert_into_random = $dbh->prepare("INSERT INTO Random_region_lookup_table_TEMP (Generation_number, Place_key) VALUES (?,?)");

  my $nregions = $number_of_gov_regions;  

  my %seen;
  
  for my $generation (1..$number_of_replicates) {
    my @members = random_subset_X($nregions, $number_of_replicates); # 5 element subsets, e.g.
    my $key = join(" ", @members); # note: members already sorted
    redo if $seen{$key}; # make sure the subsets are unique
    $seen{$key} = 1;
    print "\n\nI'm about to enter the insert subset subroutine\n\n";
    insert_subset($sth_insert_into_random, $generation, @members);
  }