package ETL;
use strict;
use warnings;
use Exporter qw<import>;
our @EXPORT_OK = qw<transform>;

sub transform {
  my ($data) = @_;
  my %new_score;

  foreach my $score ( keys %{ $data } ) {
      $new_score{ lc $_ } = $score foreach ( @{ $data->{ $score } } );
  }

  return \%new_score;
}

1;