title: Dart, get all n number letter values from a list
body: <p>Let's say I have a list</p>
  <pre><code>List test = ['hello', 'two', 'mountain', 'day',  'tomorrow', 'bye', 'sad', 'yesterday'];
  
  ExpectedResult = ['two', 'day', 'bye', 'sad'];
  </code></pre>
  <p>I want to extract all values from a list that are of certain number of characters long, in this case all result words that I'm looking have three characters, is there a simple way of doing this?</p>