'Set the Doughnut chart hole size.
Args:
size: 10 <= size <= 90.
Returns:
Nothing.'

def set_hole_size(self, size):

    if (size is None):
        return
    if ((size < 10) or (size > 90)):
        warn(('Chart    hole    size    %d    outside    Excel    range:    10    <=    size    <=    90' % size))
        return
    self.hole_size = int(size)
