def validate_width_height(dims):
    """
    Checks if dims (width, height) is a valid specification,
    meaning width and height are both integers above zero.

    :param dims: (width, height)
    :raises: TypeError, ValueError
    :returns: True
    """
    if dims is None:
        raise ValueError('Null input for (width, height).')
    width, height = dims
    if not isinstance(width, int):
        raise TypeError('Width should be an integer.')
    if not isinstance(height, int):
        raise TypeError('Height should be an integer.')
    if width < 1:
        raise ValueError('Width should be >= 1.')
    if height < 1:
        raise ValueError('Height should be >= 1.')
    return True
