Fixed regressions from 36ded015.

from django.db.models.sql.aggregates import Aggregate, Count

from django.db.models.sql import aggregates

from django.db.models.sql.aggregates import *  # NOQA

from django.contrib.gis.db.models.fields import GeometryField

__all__ = ['Count', 'Collect', 'Extent', 'Extent3D', 'MakeLine', 'Union']

__all__ = ['Collect', 'Extent', 'Extent3D', 'MakeLine', 'Union'] + aggregates.__all__

class GeoAggregate(Aggregate):

from django.db.models.fields import IntegerField, FloatField

__all__ = ['Aggregate', 'Avg', 'Count', 'Max', 'Min', 'StdDev', 'Sum', 'Variance']

# Fake fields used to identify aggregate types in data-conversion operations.

ordinal_aggregate_field = IntegerField()

computed_aggregate_field = FloatField()