} elsif ($attachment_filename && $self->{"${prefix}number"}) {
$attachment_filename .= "_" . $self->{"${prefix}number"} . $self->get_extension_for_format();
} elsif ($attachment_filename && $self->{"${prefix}number"}) {
$attachment_filename .= "_" . $self->{"${prefix}number"} . $self->get_extension_for_format();