Validates error statuses.

def _check_status(status):
        """
        Validates error statuses.
        """
        if status == 'ZERO_RESULTS':
            # When there are no results, just return.
            return
        if status == 'OVER_QUERY_LIMIT':
            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.'
            )
        elif status == 'REQUEST_DENIED':
            raise GeocoderQueryError(
                'Your request was denied.'
            )
        elif status == 'INVALID_REQUEST':
            raise GeocoderQueryError('Probably missing address or latlng.')
        else:
            raise GeocoderQueryError('Unknown error.')