def _transform(self, srid=None):
        args, geo_field = self._spatial_setup('transform')
        if not srid:
            return args['geo_col']
        try:
            # Django 1.8
            self.query.add_context('transformed_srid', srid)
        except __HOLE__:
            # Django<=1.7
            self.query.transformed_srid = srid
        return '%s(%s, %s)' % (args['function'], args['geo_col'], srid)
dataset/ETHPy150Open bkg/django-spillway/spillway/query.py/GeoQuerySet._transform