yahoo grants you a personal , non-transferable and non-exclusive right and license to use the object code of its software on a single computer ; provided that you do not -lrb- and do not allow any third party to -rrb- copy , modify , create a derivative work from , reverse engineer , reverse assemble or otherwise attempt to discover any source code , sell , assign , sublicense , grant a security interest in or otherwise transfer any right in the software .