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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 page(self):
 """ Get current page. :return int: page number """

        if not self._page:
            try:
                self._page = self.paginator.page(
                    self.query_dict.get('page', 1))
            except InvalidPage:
                raise HttpError("Invalid page", status=HTTP_400_BAD_REQUEST)
        return self._page