sub log {
        my ($self, $msg, $log) = @_;

        my $log_fh;

        if (defined $log && ref $log ne 'GLOB'){
            # filename sent in
            open my $fh, '>>', $log or die $!;
            $log_fh = $fh;
        }
        elsif (defined $log && ref $log eq 'GLOB'){
            # file handle sent in
            $log_fh = $log;
        }
        else {
            # use the default fh
            $log_fh = $self->{default_log};
        }