title: Concatenate elements of a list
body: <p>I have a list like <code>l=['a', 'b', 'c']</code>
  I want a String like 'abc'. So in fact the result is <code>l[0]+l[1]+l[2]</code>, which can also be writte as</p>
  
  <pre><code>s = ''
  for i in l:
      s += i
  </code></pre>
  
  <p>Is there any way to do this more elegantly?</p>