def increment(self, version_number_idx: int, increment: int):
        """
        increment the version number with `n` at index `i`.
        >>> from Redy.Tools.Version import Version
        >>> a = Version('1.0.0.2')
        >>> a.increment(version_number_idx=2, increment=1)
        >>> assert a == ('1.0.1.0')
        >>> print(a[0])
        >>> a[0] = 2
        """
        _numbers = list(self._numbers)
        _numbers[version_number_idx] += increment
        for each in range(version_number_idx + 1, len(_numbers)):
            _numbers[each] = 0
        self._numbers = tuple(_numbers)