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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, log=values.unset, message_date_before=values.unset, message_date=values.unset, message_date_after=values.unset, page_token=values.unset, page_number=values.unset, page_size=values.unset):
 """ Retrieve a single page of NotificationInstance records from the API. Request is executed immediately :param unicode log: Filter by log level :param date message_date_before: Filter by date :param date message_date: Filter by date :param date message_date_after: Filter by date :param str page_token: PageToken provided by the API :param int page_number: Page Number, this value is simply for client state :param int page_size: Number of records to return, defaults to 50 :returns: Page of NotificationInstance :rtype: twilio.rest.api.v2010.account.call.notification.NotificationPage """

        params = values.of({
            'Log': log,
            'MessageDate<': serialize.iso8601_date(message_date_before),
            'MessageDate': serialize.iso8601_date(message_date),
            'MessageDate>': serialize.iso8601_date(message_date_after),
            'PageToken': page_token,
            'Page': page_number,
            'PageSize': page_size,
        })

        response = self._version.page(
            'GET',
            self._uri,
            params=params,
        )

        return NotificationPage(self._version, response, self._solution)