THE PROBLEM

Extract the XML string from a text file formatted like this:

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0000000020: 3c3f786d 6c207665 7273696f 6e3d2231 2e30223f '<?xml version="1.0"?'
0000000040: 3e0a3c4d 65737361 67653e0a 3c49643e 3939373c '>.<Message>.<Id>997<'
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THE SOLUTION

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#!/usr/bin/perl
use strict;
open H, shift || 'filename.txt' or die "Error: $!\n";
print pack "(H*)*", map{s/^\d+:| |'.+?'\n?$//g && $_}<H>;
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