Helper method to get geometries within a certain bounds (as WKT).

        Returns GeoJSON (loaded as a list of python dictionaries).

def get_geoms_for_bounds(self, bounds):
        """
        Helper method to get geometries within a certain bounds (as WKT).

        Returns GeoJSON (loaded as a list of python dictionaries).
        """
        poly = ogr.CreateGeometryFromWkt(bounds)
        self._layer.SetSpatialFilter(poly)
        poly.Destroy()

        return [json.loads(e.GetGeometryRef().ExportToJson()) for e in self._layer]