title: How to delete thread messages on Slack?
body: <p>I am trying to delete lots of messages on Slack.
  Those messages are in a thread.</p>
  
  <p>Because there are proximately 800 messages to be deleted, so I want to automate the processing.</p>
  
  <p>So far I tried API delete function. I executed the following command:</p>
  
  <p><code>$ curl -XPOST -d 'token=MY_TOKEN' -d 'channel=MY_CHANNEL' -d 'ts=TS_VALUE' 'https://slack.com/api/chat.delete'</code></p>
  
  <p>But the command deleted only the root message, not all threading messages.</p>
  
  <p>Also I tried to use slack-cleaner with the following command,</p>
  
  <p><code>$ slack-cleaner --token '&lt;my_token&gt;' --message --direct '&lt;my_channel&gt;' --user '*'</code></p>
  
  <p>This resulted in a python error saying </p>
  
  <p><code>AttributeError: 'dict' object has no attribute 'iteritems'</code></p>
  
  <p>How can I delete 800 messages in a thread?</p>