I'm playing around with learning racket in an org buffer and I have a bunch
of blocks that look like this

   #+begin_src racket :var value="abbracadaabra"
   ...do stuff with value...
   #+end_src


   #+begin_src racket :var value="abbracadaabra"
   ...do other stuff with value...
   #+end_src

Is there a way to move the "abbracadaabra" string into a single location so
that I can just pull the var from that? I know I can put it in a table or a
list, but how about into a single value?