present_code => sub { 
                     
     my $data = $_[0];

     $data =~ s@&lab;@<post_inc>common/lab</post_inc>@gs;          
     $data =~ s@&rab;@<post_inc>common/rab</post_inc>@gs;
     $data =~ s@&lsb;@<post_inc>common/lsb</post_inc>@gs;
     $data =~ s@&rsb;@<post_inc>common/rsb</post_inc>@gs;
     $data =~ s@&lcb;@<post_inc>common/lcb</post_inc>@gs;
     $data =~ s@&rcb;@<post_inc>common/rcb</post_inc>@gs;
 
     return $data;
    }