code: def add_tag(self, new_tags):
          
  
          tags = self.get_tags()
          orig_tag_cnt = len(tags)
          # print("self.get_tags() {}".format(tags))
  
          if isinstance(new_tags, six.string_types):
              new_tags = new_tags.split(',')
              # print("spliting tags :: {}".format(new_tags))
  
          for tag in new_tags:
              if not tag in tags:
                  tags.append(tag.strip())
  
          if len(tags) > orig_tag_cnt:
              xml_tags = escape(",".join(tags))
              post_data = TAGS_TEMPLATE.format(connectware_id=self.get_connectware_id(),
                                               tags=xml_tags)
              self._conn.put('/ws/DeviceCore', post_data)
  
              # Invalidate cache
              self._device_json = None
docs: Add a tag to existing device tags. This method will not add a duplicate, if already in the list.
  
          :param new_tags: the tag(s) to be added. new_tags can be a comma-separated string or list