self.pm provides $self and @args for your Perl OO modules, so you don't need to
say:

    my $self = shift;

And this is no source filter.

INSTALLATION

To install this module, run the following commands:

    perl Makefile.PL
    make
    make test
    make install

COPYRIGHT AND LICENCE

Copyright (C) 2021 Kang-min Liu

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.