def geocode(self, query, exactly_one=True, timeout=DEFAULT_SENTINEL,
                out_fields=None):
        """
        Return a location point by address.

        :param str query: The address or query you wish to geocode.

        :param bool exactly_one: Return one result or a list of results, if
            available.

        :param int timeout: Time, in seconds, to wait for the geocoding service
            to respond before raising a :class:`geopy.exc.GeocoderTimedOut`
            exception. Set this only if you wish to override, on this call
            only, the value set during the geocoder's initialization.

        :param out_fields: A list of output fields to be returned in the
            attributes field of the raw data. This can be either a python
            list/tuple of fields or a comma-separated string. See
            https://developers.arcgis.com/rest/geocode/api-reference/geocoding-service-output.htm
            for a list of supported output fields. If you want to return all
            supported output fields, set ``out_fields="*"``.

            .. versionadded:: 1.14.0
        :type out_fields: str or iterable

        :rtype: ``None``, :class:`geopy.location.Location` or a list of them, if
            ``exactly_one=False``.
        """
        params = {'singleLine': self.format_string % query, 'f': 'json'}
        if exactly_one:
            params['maxLocations'] = 1
        if out_fields is not None:
            if isinstance(out_fields, string_compare):
                params['outFields'] = out_fields
            else:
                params['outFields'] = ",".join(out_fields)
        url = "?".join((self.api, urlencode(params)))
        logger.debug("%s.geocode: %s", self.__class__.__name__, url)
        response = self._call_geocoder(url, timeout=timeout)

        # Handle any errors; recursing in the case of an expired token.
        if 'error' in response:
            if response['error']['code'] == self._TOKEN_EXPIRED:
                self.retry += 1
                self._refresh_authentication_token()
                return self.geocode(
                    query, exactly_one=exactly_one, timeout=timeout
                )
            raise GeocoderServiceError(str(response['error']))

        # Success; convert from the ArcGIS JSON format.
        if not len(response['candidates']):
            return None
        geocoded = []
        for resource in response['candidates']:
            geometry = resource['location']
            geocoded.append(
                Location(
                    resource['address'], (geometry['y'], geometry['x']), resource
                )
            )
        if exactly_one:
            return geocoded[0]
        return geocoded