Validates error statuses.

def _check_status(status):
        """
        Validates error statuses.
        """
        status_code = status['code']
        if status_code == 429:
            # Rate limit exceeded
            raise GeocoderQuotaExceeded(
                'The given key has gone over the requests limit in the 24'
                ' hour period or has submitted too many requests in too'
                ' short a period of time.'
            )
        if status_code == 200:
            # When there are no results, just return.
            return

        if status_code == 403:
            raise GeocoderQueryError(
                'Your request was denied.'
            )
        else:
            raise GeocoderQueryError('Unknown error.')