title: Python itertools.product with variable number of arguments
body: <p>I am trying to write a module to combine a variable number of lists using itertools.product.</p>
  
  <p>The closest I can get is:</p>
  
  <pre><code>import itertools
  lists = [["item1","item2"],["A","b","C"], ["etc..."]]
  searchterms = list(itertools.product(lists))
  print searchterms
  </code></pre>
  
  <p>This doesn't work, because lists is a single list, so it just returns the original sequence. But I can't figure out how to pass each element of the lists variable to itertools. </p>
  
  <p>Thanks for any suggestions.</p>