title: Get nearest time previous to current time which is divisible by 5
body: <p>I have a dataframe with a column which have time data in the format HH:MM:SS. Sample data is shown below for reference:</p>
  
  <pre><code>Time
  09:25:03
  09:28:40
  09:36:12
  09:36:14
  09:41:10
  09:51:00
  09:58:48
  10:00:11
  10:00:17
  10:21:44
  10:21:53
  10:32:58
  11:08:59
  11:45:55
  11:49:14
  12:18:54
  12:21:22
  13:05:47
  13:19:37
  13:19:57
  13:25:22
  14:21:10
  </code></pre>
  
  <p>I want to get the nearest time previous to current time which is divisible by 5. I want the output like below:</p>
  
  <pre><code>Time        Nearest_Time
  09:25:03    09:25:00
  09:28:40    09:25:00
  09:36:12    09:35:00
  09:36:14    09:35:00
  09:41:10    09:40:00
  09:51:00    09:50:00
  09:58:48    09:50:00
  10:00:11    10:00:00
  10:00:17    10:00:00
  10:21:44    10:20:00
  10:21:53    10:20:00
  10:32:58    10:30:00
  11:08:59    11:05:00
  11:45:55    11:45:00
  11:49:14    11:45:00
  12:18:54    12:15:00
  12:21:22    12:20:00
  13:05:47    13:05:00
  13:19:37    13:15:00
  13:19:57    13:15:00
  13:25:22    13:25:00
  14:21:10    14:20:00
  </code></pre>