def unionagg(self, **kwargs):
        return self._spatial_aggregate(aggregates.Union, **kwargs)

    ### Private API -- Abstracted DRY routines. ###
Performs an aggregate union on the given geometry field.  Returns
dataset/ETHPy150Open CollabQ/CollabQ/vendor/django/contrib/gis/db/models/query.py/GeoQuerySet.unionagg