code: public ApiClient setDateFormat(DateFormat dateFormat) {
      this.dateFormat = dateFormat;
      // Also set the date format for model (de)serialization with Date properties.
      this.objectMapper.setDateFormat((DateFormat) dateFormat.clone());
      // Need to rebuild the Client as objectMapper changes.
      rebuildHttpClient();
      return this;
    }
docs: Set the date format used to parse/format date parameters.
  
  @param dateFormat Date format
  @return API client