/usr/share/perl5/GO/Parsers/obo_parser.pm is in libgo-perl 0.15-5.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | package GO::Parsers::obo_parser;
use base qw(GO::Parsers::obo_text_parser);
1;
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