client.go
func (c *Client) Unsubscribe(ch chan *Event) {
	c.mu.Lock()
	defer c.mu.Unlock()

	if c.subscribed[ch] != nil {
		c.subscribed[ch] <- true
	}
}
func (c *Client) Unsubscribe(ch chan *Event) {
	c.mu.Lock()
	defer c.mu.Unlock()

	if c.subscribed[ch] != nil {
		c.subscribed[ch] <- true
	}
}
// Unsubscribe unsubscribes a channel