title: Round off some values of a tuple
body: <p>I have tuples like this (  I not sure will it call a list of tuple or not ! )</p>
  
  <pre><code>ratings = [('5', 45.58139534883721), ('4', 27.44186046511628), ('3', 20.0), ('2', 5.116279069767442), ('1', 1.8604651162790697)]
  </code></pre>
  
  <p>I want to make second value round off ( or truncate, don't matter to me )up to 2 decimal place, like this:</p>
  
  <pre><code>[('5', 45.58), ('4', 27.44), ('3', 20.0), ('2', 5.11), ('1', 1.86)]
  </code></pre>
  
  <p>I tried something like this:</p>
  
  <pre><code>l = tuple([round(x,2) if isinstance(x, float) else x for x in ratings])
  </code></pre>
  
  <p>But this seems to be not working. What can I try?</p>