title: how to get string value from a list in python
body: <pre><code>result = [{'start_date': datetime.date(2019, 1, 20)}, {'start_date': datetime.date(2019, 1, 21)}]
  </code></pre>
  
  <p>I want to get output like in list format:</p>
  
  <pre><code>result = ['2019-1-20', '2019-1-21']
  </code></pre>