code: private BaseException createException(int httpStatusCode, JsonContent jsonContent) {
          return unmarshallers.stream()
                  .filter(u -> u.matches(httpStatusCode))
                  .findFirst()
                  .map(u -> safeUnmarshall(jsonContent, u))
                  .orElseThrow(this::createUnknownException);
      }
docs: Create an AmazonServiceException using the chain of unmarshallers. This method will never
  return null, it will always return a valid exception.
  
  @param httpStatusCode Http status code to find an appropriate unmarshaller
  @param jsonContent    JsonContent of HTTP response
  @return Unmarshalled exception