Return URL for next page.

        :return str:

def next_page(self):
        """ Return URL for next page.

        :return str:

        """
        if self.page.has_next():
            self.query_dict['page'] = self.page.next_page_number()
            return "%s?%s" % (self.path, urlencode(self.query_dict))
        return ""