/usr/lib/ is in libdate-pcalc-perl 6.1-4build1.
This file is owned by root:root, with mode 0o755.
..
/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/Date/
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalc.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalendar.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalc/
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalc/Object.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalc/Object.pod
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalendar/
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalendar/Year.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalendar/Profiles.pod
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalendar/Year.pod
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalendar/Profiles.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalendar.pod
/usr/lib/x86_64-linux-gnu/perl5/5.22/Date/Pcalc.pod
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Date/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Date/Pcalc/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Date/Pcalc/Pcalc.so