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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, iso_code=values.unset, continent=values.unset, country_code=values.unset, low_risk_numbers_enabled=values.unset, high_risk_special_numbers_enabled=values.unset, high_risk_tollfraud_numbers_enabled=values.unset, page_token=values.unset, page_number=values.unset, page_size=values.unset):
 """ Retrieve a single page of CountryInstance records from the API. Request is executed immediately :param unicode iso_code: Filter to retrieve the country permissions by specifying the ISO country code :param unicode continent: Filter to retrieve the country permissions by specifying the continent :param unicode country_code: Country code filter :param bool low_risk_numbers_enabled: Filter to retrieve the country permissions with dialing to low-risk numbers enabled :param bool high_risk_special_numbers_enabled: Filter to retrieve the country permissions with dialing to high-risk special service numbers enabled :param bool high_risk_tollfraud_numbers_enabled: Filter to retrieve the country permissions with dialing to high-risk toll fraud numbers enabled :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 CountryInstance :rtype: twilio.rest.voice.v1.dialing_permissions.country.CountryPage """

        params = values.of({
            'IsoCode': iso_code,
            'Continent': continent,
            'CountryCode': country_code,
            'LowRiskNumbersEnabled': low_risk_numbers_enabled,
            'HighRiskSpecialNumbersEnabled': high_risk_special_numbers_enabled,
            'HighRiskTollfraudNumbersEnabled': high_risk_tollfraud_numbers_enabled,
            'PageToken': page_token,
            'Page': page_number,
            'PageSize': page_size,
        })

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

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