code: def delete_subject(self, subject):
          
  
          url = '/'.join([self.url, 'subjects', subject])
  
          result, code = self._send_request(url, method="DELETE")
          if not (code >= 200 and code <= 299):
              raise ClientError('Unable to delete subject: {}'.format(result))
          return result
docs: DELETE /subjects/(string: subject)
          Deletes the specified subject and its associated compatibility level if registered.
          It is recommended to use this API only when a topic needs to be recycled or in development environments.
          :param subject: subject name
          :returns: version of the schema deleted under this subject
          :rtype: (int)