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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 the next `Page` after this one in the result sequence it's from. If the current page is the last page in the sequence, calling this method raises a `ValueError`. """

        try:
            next_url = self.next_url
        except AttributeError:
            raise PageError("Page %r has no next page" % self)
        return self.page_for_url(next_url)