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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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 ""