#!/usr/bin/perl
use strict;
use warnings;
my (@new_data, @old_data);
open (DATA, '<old_data.txt') || die $!;
    while (<DATA>) { push @old_data, $_ };
close DATA;
foreach my $i (@old_data) {
    my @pairs = split(/,/, $i);
    my @singles;
    foreach my $i (@pairs) {
        my ($l, $r) = split(/=/, $i);
        push @singles, $r;
    }
    my $family = join(' ', @singles);
    push @new_data, $family;
}
open (DATA, '>new_data.txt') || die $!;
    foreach (@new_data) { print DATA $_ }
close DATA;