title: Generate combinations of elements from multiple lists
body: <p>I'm making a function that takes a variable number of lists as input (i.e., an <a href="http://docs.python.org/2/tutorial/controlflow.html#arbitrary-argument-lists" rel="nofollow">arbitrary argument list</a>).
  I need to compare each element from each list to each element of all other lists, but I couldn't find any way to approach this.</p>