Convert subpage & subitem to a integer

    * if page == 1, then return 0, since the item count is the true # of items
    * if page == 2, then return, page-1 * items_per_page, since we are
      returning the # of items on a full page.

    Args:
        * None

    Returns:
        * Integer - Which represents the number of items up to the page.

def pi_to_number(self, page=1, item=1):
        """
    Convert subpage & subitem to a integer

    * if page == 1, then return 0, since the item count is the true # of items
    * if page == 2, then return, page-1 * items_per_page, since we are
      returning the # of items on a full page.

    Args:
        * None

    Returns:
        * Integer - Which represents the number of items up to the page.
        """
        if page > 1:
            return ((page - 1) * self.page_items) + item
        else:
            return 0 + item