code: def remove_tag(self, tag):
          
  
          tags = self.get_tags()
          tags.remove(tag)
  
          post_data = TAGS_TEMPLATE.format(connectware_id=self.get_connectware_id(),
                                           tags=escape(",".join(tags)))
          self._conn.put('/ws/DeviceCore', post_data)
  
          # Invalidate cache
          self._device_json = None
docs: Remove tag from existing device tags
  
          :param tag: the tag to be removed from the list
  
          :raises ValueError: If tag does not exist in list