title: Returning all "positions" of a list
body: <p>I Have a list with "a" and "b" and the "b"'s are somewhat of a path and "a"'s are walls. Im writing a program to make a graph of all the possible moves. I got the code running to check the first "b" for possible moves, but i have NO Idea how im going to find all "b"'s , even less check them all without repeating.</p>
  
  <p>Major issue im having is getting the tuple coordinates of the "b"'s out of the list.</p>
  
  <p>Any pointers/tips?</p>