@classmethod
    def geo_distance(cls, field, center, distance, distance_type=None):

        instance = cls(geo_distance={'distance': distance, field: center})
        if distance_type is not None:
            instance['geo_distance']['distance_type'] = distance_type
        return instance
http://www.elasticsearch.org/guide/reference/query-dsl/geo-distance-filter.html
dataset/ETHPy150Open ooici/elasticpy/elasticpy/filter.py/ElasticFilter.geo_distance