pagination

pagination.py

    def paginate(self, items, endpoint, is_prev=None, is_next=None,
                 url_args=None, finish_args=None):
        url_args = url_args or {}
        finish_args = finish_args or {}
        is_update = True
        try:
            current_page = self.request.args.get('page')[0]
        except TypeError:
            is_update = False
            current_page = 0

        if is_next:
            next_page = str(int(current_page) + 1)
            items.insert(0, {
                'label': 'Next >>',
                'path': self.url_for(endpoint, page=next_page, **url_args)
            })

        if is_prev:
            prev_page = str(int(current_page) - 1)
            items.insert(0, {
                'label': '<< Previous',
                'path': self.url_for(endpoint, page=prev_page, **url_args)
            })

        return self.finish(items, update_listing=is_update, **finish_args)

would you mind adding comments to this? This seems like something I need to use in my project and a little help understanding it would be greatly appreciated.