title: How to join entries in a set into one string?
body: <p>Basically, I am trying to join together the entries in a set in order to output one string. I am trying to use syntax similar to the join function for lists. Here is my attempt:</p>
  
  <pre><code>list = ["gathi-109","itcg-0932","mx1-35316"]
  set_1 = set(list)
  set_2 = set(["mx1-35316"])
  set_3 = set_1 - set_2
  print set_3.join(", ")
  </code></pre>
  
  <p>However I get this error: <code>AttributeError: 'set' object has no attribute 'join'</code></p>
  
  <p>What is the equivalent call for sets? </p>