def corofunc1():
            called[0] += 1
            return event.ReturnValue(insert_events=[evt2], append_events=[evt])
def circle(self,x,y,r):
		for x_offset in range(-r,r+1):
			for y_offset in range(-r,r+1):
				if sqrt(x_offset**2+y_offset**2)<r:
					self.board[x+x_offset,y+y_offset] = self.color