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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 update_notification_settings(self, api_token, event, service, should_notify):
 """Update a user's notification settings. :param api_token: The user's login api_token. :type api_token: str :param event: Update the notification settings of this event. :type event: str :param service: ``email`` or ``push`` :type service: str :param should_notify: If ``0`` notify, otherwise do not. :type should_notify: int :return: The HTTP response to the request. :rtype: :class:`requests.Response` """

        params = {
            'token': api_token,
            'notification_type': event,
            'service': service,
            'dont_notify': should_notify
        }
        return self._post('update_notification_setting', params)