code: def check_captcha(self, captcha, value, id=None):
          
          payload = {'captcha': captcha,
                     'value': value,
                     'id': id}
          r = self.request('get', 'http://cleanweb-api.yandex.ru/1.0/check-captcha', params=payload)
          root = ET.fromstring(r.content)
          if root.findall('ok'):
              return True
          if root.findall('failed'):
              return False
docs: http://api.yandex.ru/cleanweb/doc/dg/concepts/check-captcha.xml