How to use the @commercetools-frontend/ui-kit.NumberInput.isEmpty function in @commercetools-frontend/ui-kit

: { hasForbiddenChars: true };
      return {
        ...acc,
        [language]: value,
      };
    }, {});

    errors.slug.translations = translationErrors;
  }

  // validate description
  if (MultilineTextInput.isEmpty(formValues.description))
    errors.description.missing = true;

  // validate inventory
  if (NumberInput.isEmpty(formValues.inventory)) {
    errors.inventory.missing = true;
  } else {
    // When the value is not empty, we can assume that it is a number
    if (formValues.inventory < 0) errors.inventory.negative = true;
    if (NumberInput.hasFractionDigits(formValues.inventory))
      errors.inventory.fractions = true;
  }

  // validate price
  if (MoneyInput.isEmpty(formValues.price)) {
    errors.price.missing = true;
  } else if (MoneyInput.isHighPrecision(formValues.price, locale)) {
    errors.price.unsupportedHighPrecision = true;
  }

  // Formik will think there are errors when the object returned as a

description: {},
    inventory: {},
    price: {},
  };

  // validate key
  // Input elements usually provide a way to check whether it's value is empty
  // This is useful to determine whether a required value was not filled out.
  if (TextInput.isEmpty(formValues.key)) errors.key.missing = true;

  // validate description
  if (MultilineTextInput.isEmpty(formValues.description))
    errors.description.missing = true;

  // validate inventory
  if (NumberInput.isEmpty(formValues.inventory)) {
    errors.inventory.missing = true;
  } else {
    // When the value is not empty, we can assume that it is a number
    if (formValues.inventory < 0) errors.inventory.negative = true;
    if (NumberInput.hasFractionDigits(formValues.inventory))
      errors.inventory.fractions = true;
  }

  // validate price
  if (MoneyInput.isEmpty(formValues.price)) {
    errors.price.missing = true;
  } else if (MoneyInput.isHighPrecision(formValues.price, locale)) {
    errors.price.unsupportedHighPrecision = true;
  }

  // Formik will think there are errors when the object returned as a