code: private boolean isEmailPropertiesSet() {
          return properties != null &&
                  properties.containsKey(EMAIL_HOST) &&
                  properties.containsKey(EMAIL_PORT) &&
                  properties.containsKey(EMAIL_USERNAME) &&
                  properties.containsKey(EMAIL_PASSWORD) &&
                  properties.containsKey(EMAIL_FROM) &&
                  properties.containsKey(EMAIL_TO);
      }
docs: This function will check if all the minimum
  required email properties are set,
  that can facilitate sending of exported
  sql to email
  @return bool