def METHOD_NAME(self, input_event):
    if self.running:
        return
    with self.html.lock:
        x, y = input_event.node.attributes['data-gol-id'].split(':')
        x = int(x)
        y = int(y)
        # set data
        self.data[y][x] = not self.data[y][x]
        # set cell
        cell = self.board.nodes[y][x]
        cell.alive = not cell.alive