title: how to use dataframe between_time() function
body: <p>I am trying to use the <code>between_time</code> function. I have formatted the string type time to datetime</p>
  
  <pre><code>dataset['TimeStamp'] = pd.to_datetime(dataset['TimeStamp'],format)
  </code></pre>
  
  <p>and I defined search start time and end time:</p>
  
  <pre><code>start = datetime.time(9,40,0)
  
  end = datetime.time(10,00,0)
  </code></pre>
  
  <p>then I call <code>dataset['TimeStamp'].between_time(start, end)</code></p>
  
  <p>This is the error I get:</p>
  
  <pre><code>TypeError: Index must be DatetimeIndex
  </code></pre>
  
  <p>Please how can I fix it. Thank you</p>