/usr/lib/ is in libmath-random-isaac-xs-perl 1.004-2build1.
This file is owned by root:root, with mode 0o755.
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/usr/lib/x86_64-linux-gnu/perl5/5.22/Math/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/perl5/
/usr/lib/x86_64-linux-gnu/perl5/5.22/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Math/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Math/Random/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Math/Random/ISAAC/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Math/Random/ISAAC/XS/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Math/Random/ISAAC/XS/XS.so
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Math/Random/ISAAC/XS/XS.bs
/usr/lib/x86_64-linux-gnu/perl5/5.22/Math/Random/
/usr/lib/x86_64-linux-gnu/perl5/5.22/Math/Random/ISAAC/
/usr/lib/x86_64-linux-gnu/perl5/5.22/Math/Random/ISAAC/XS.pm