title: Extract second tuple element in list of tuples
body: <p>I have a Map where each value is a list of Tuples such as:</p>
  
  <pre><code>List(('a',1), ('b', 4), ('c', 3)....)
  </code></pre>
  
  <p>what is the most scala-thonic way to change each value is still a LIst but is only the second element of each Tuple</p>
  
  <pre><code>List(1,4,3)
  </code></pre>
  
  <p>I have tried</p>
  
  <pre><code>myMap.mapValues(x =&gt; x._2)
  </code></pre>
  
  <p>And I get </p>
  
  <pre><code>error: value _2 is not a member of List[(Char, Integer)]
  </code></pre>
  
  <p>any tips?</p>