code: public static <T> T unmarshal(InputStream is, ObjectMapper mapper) {
     return unmarshal(is, mapper, Collections.<String, String>emptyMap());
    }
docs: Unmarshals a stream.
  @param is      The {@link InputStream}.
  @param mapper  The {@link ObjectMapper} to use.
  @param <T>     The target type.
  @return returns de-serialized object
  @throws KubernetesClientException KubernetesClientException