use strict;
use warnings;
use Text::CSV;

my @data;   # 2D array for CSV data
my %dict=();

my $file = 'AMS.csv';
my $csv = Text::CSV->new({ binary => 1, quote_null => 0 });
open my $fh, '<', $file or die "Could not open $file: $!";

while( my $ar = $csv->getline( $fh ) ) { 
  if (@$ar > 2){
    push @data,$ar;
  } elsif (@$ar == 2) {
    $dict{$ar->[0]} = $ar->[1];    
  }
}

open $fh, ">:encoding(utf8)", "PPS.csv" or die "PPS.csv: $!";
for my $ar (@data) {
  $ar->[0] = $dict{$ar->[0]};
  $ar->[-1] = $dict{$ar->[-1]};
  $csv->print($fh, $ar);
  print $fh "\n";
}
close $fh or die "PPS.csv: $!";
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