Save the base layer on model

[Mario8k]

Hi,
if i use in the admin, GeoModelAdmin class. There is a way to obtain
the base layer and store it in a baselayer field of the model?

Supose in admin class i put:

class MyAdmin(GeoModelAdmin):

options = {
'layers': ['osm.mapnik','google.streets'],
}

Then, i want to store the value of the layer choosed (with the layer
switcher control), in my model class. This is for use later, when I'm
editing, to remember the previous selection.

class MyModel(models.Model):
circuit = models.LineStringField()
baselayer = models.CharField()

How can i achieve this? any idea? Thanks.