code: def content_type(self, response):
          
          if not re_html.match(response.headers.get('Content-Type').decode('utf-8')):
              self.log.warn(
                  "Dropped: %s's content is not of type "
                  "text/html but %s", response.url, response.headers.get('Content-Type')
              )
              return False
          else:
              return True
docs: Ensures the response is of type
  
          :param obj response: The scrapy response
          :return bool: Determines wether the response is of the correct type