title: Python tuples sorting based on last element
body: <p>Here is my question i have <code>tuple1=[(1, 3), (3, 2), (2, 1)]</code> i want to sort tuple based on last digit of each tuple so the resultant will look like this 
  <code>output=[(2, 1), (3, 2), (1, 3)]</code>
  below is my code </p>
  
  <pre><code>    i=0
  for x in tuples:
      c.append(x[len(x)-1])
      last=sorted(c)
      for y in last.iteritems():
          if(y in x[len(x)-1]):
              print x             
              #b.insert(i,x)
  i=i+1
  </code></pre>
  
  <p>after running iam getting an error message </p>
  
  <pre><code>    Traceback (most recent call last):
      File "x.py", line 47, in &lt;module&gt;
     sort_last([(1, 3), (3, 2), (2, 1)])
    File "x.py", line 35, in sort_last
   if(y in x[len(x)-1]):
    TypeError: argument of type 'int' is not iterable
  </code></pre>