def tearDown(self):
        super(SimpleInstanceTest, self).tearDown()
        CONF.network_label_regex = self.orig_conf
        CONF.ip_start = None
def __init__(self, w, h, color = "empty"):
		self.board = zeros((h,w), dtype=uint8)
		self.w = w
		self.h = h
		self.set_brush(color)