def run_user_block(extractor, response, body, &block)
      header = extractor.extract_header_data(response)
      case block.arity
        when 1 then yield(header)
        when 2 then yield(header, body)
        else
          raise AdsCommon::Errors::ApiException,
              "Wrong number of block parameters: %d" % block.arity
      end
      return nil
    end
def run_user_block(extractor, response, body, &block)
      header = extractor.extract_header_data(response)
      case block.arity
        when 1 then yield(header)
        when 2 then yield(header, body)
        else
          raise AdsCommon::Errors::ApiException,
              "Wrong number of block parameters: %d" % block.arity
      end
      return nil
    end
Yields to user-specified block with additional information such as
 headers.