code: def forum_post_update(self, topic_id, body):
          
          params = {'forum_post[body]': body}
          return self._get('forum_posts/{0}.json'.format(topic_id), params,
                           method='PUT', auth=True)
docs: Update a specific forum post (Requries login)(Moderator+)(UNTESTED).
  
          Parameters:
              post_id (int): Forum topic id.
              body (str): Post content.