/usr/share/perl5/Slic3r/Fill/ArchimedeanChords.pm is in slic3r 1.1.7+dfsg-2+b1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 | package Slic3r::Fill::ArchimedeanChords;
use Moo;
extends 'Slic3r::Fill::PlanePath';
use Math::PlanePath::ArchimedeanChords;
1;
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