title: python convert strings into sets of characters
body: <pre><code>c=['a,b,c','a,b,c','a,b']
  for item in c:
      a=set(item.replace("'",""))
      b=list(a)
  print b
  </code></pre>
  
  <p>It returns: </p>
  
  <pre><code>['a','b',',']
  </code></pre>
  
  <p>What I want is : </p>
  
  <pre><code>['a','b','c']
  </code></pre>
  
  <p>How do I convert these strings into sets of characters? </p>