Fixed the duplicate slots view.
The script would not clear the screen upon recalculation also the list of duplicates would increase with every iteration because the variables weren't properly reset.
Patch by: Merio Ferraro, Lennard de Rijk
Reviewed by: to-be-reviewed
# Getting the normal admin routines, classes, and `site` instance.
from django.contrib.admin import autodiscover, site, StackedInline, TabularInline, HORIZONTAL, VERTICAL
# Geographic admin options classes and widgets.
from django.contrib.gis.admin.options import GeoModelAdmin
from django.contrib.gis.admin.widgets import OpenLayersWidget
try:
from django.contrib.gis.admin.options import OSMGeoAdmin
HAS_OSM = True
except ImportError:
HAS_OSM = False