public function addItem(Item $item)
    {
        if ($this->items == null) {
            $this->items = [];
        }

        $this->items[] = $item;

        return $this;
    }
public function addItem(Item $item)
    {
        if ($this->items == null) {
            $this->items = [];
        }

        $this->items[] = $item;

        return $this;
    }
@param Item $item

@return Cart