useful for additional extras, like Dinner Tickets.

            ``RENDER_TYPE_ITEM_QUANTITY`` shows a select menu to select a

            Product type, and an input field, where the user can specify the

            quantity for that Product type. This is useful for categories that

            have a lot of options, from which the user is not going to select

            all of the options.

        limit_per_user (Optional[int]): This restricts the number of items

            from this Category that each attendee may claim. This extends

            across multiple Invoices.

            available. By convention, your Category for ticket types should

            have the lowest display order.

    '''

    class Meta:

        app_label = "registrasion"

        verbose_name = _("inventory - category")

        verbose_name_plural = _("inventory - categories")

        ordering = ("order", )

    def __str__(self):

        return self.name

            applied.

        limit_per_user (Optional[int]): This restricts the number of this

            Product that each attendee may claim. This extends across multiple

            Invoices.

        reservation_duration (datetime): When a Product is added to the user's

            tentative registration, it is marked as unavailable for a period of

            time. This allows the user to build up their registration and then

            pay for it. This reservation duration determines how long an item

            should be allowed to be reserved whilst being unpaid.

            within each Category.

    '''

    class Meta:

        app_label = "registrasion"

        verbose_name = _("inventory - product")

        ordering = ("category__order", "order")

    def __str__(self):

        return "%s - %s" % (self.category.name, self.name)