@SneakyThrows(JsonProcessingException.class)
    public static String objectToJson(Object obj) {
        return WRITER.writeValueAsString(obj);
    }
Converts an Instagram shortcode to a numeric ID.

@param code The shortcode.
@return The numeric ID.
@throws IllegalArgumentException If bad parameters are provided.
src/main/java/com/github/instagram4j/instagram4j/utils/IGUtils.java