@Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof Tag)) return false;

        Tag tag = (Tag) o;

        if (lastPurchase != null ? !lastPurchase.equals(tag.lastPurchase) : tag.lastPurchase != null)
            return false;
        if (timestamp != null ? !timestamp.equals(tag.timestamp) : tag.timestamp != null)
            return false;

        return true;
    }