docs: def clean_cookie(self):
          """Only clean the cookie from headers and return self."""
          if not self.is_cookie_necessary:
              return self
          headers = self.request.get('headers', {})
          cookies = SimpleCookie(headers['Cookie'])
          for k, v in cookies.items():
              new_cookie = '; '.join(
                  [i.OutputString() for i in cookies.values() if i != v])
              new_request = deepcopy(self.request)
              new_request['headers']['Cookie'] = new_cookie
              self._add_task('Cookie', k, new_request)
          return self