code: public function parseJson($body)
      {
          if ($body instanceof ResponseInterface) {
              $body = $body->getBody();
          }
  
          if ($body instanceof StreamInterface) {
              $body = $body->getContents();
          }
  
          if (empty($body)) {
              return false;
          }
  
          $contents = json_decode($body, true);
  
          if (JSON_ERROR_NONE !== json_last_error()) {
              throw new Exception('Failed to parse JSON: '.json_last_error_msg());
          }
  
          return $contents;
      }
docs: @param \Psr\Http\Message\ResponseInterface|string $body
  
  @return array
  
  @throws \Exception