#!/usr/bin/perl
use warnings;
use strict;

use XML::LibXML;

my $text_file = shift;

open my $In, '<', $text_file or die $!;
my $extract = join '\s+(.*?)\s*', qw( FirstName LastName Email BirthDa
+te $ );
$extract = qr/$extract/;
my %birthday;
while (<$In>) {
    my ($first, $last, $email, $bdate) = /$extract/;
    $birthday{$email} = $bdate;
}

while (my $xml_file = shift) {
    my $dom = 'XML::LibXML'->load_xml(location => $xml_file);
    my $email = $dom->findvalue('/contractor/person/email');
    unless (exists $birthday{$email}) {
        warn "No birthday for $email!\n";
        next
    }
    my $person = $dom->find('/contractor/person');
    my $bday = $person->[0]->addChild($dom->createElement('birthday'))
+;
    $bday->appendText($birthday{$email});
    $dom->toFile($xml_file);
}
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See XML::LibXML for documentation.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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