#If the 'selected_unts' has been stored, then extract self._selected_units from selections.
if 'selected_units' in selections:
self._selected_units = selections['selected_units']
#Make sure that the 'self._selected_category' has been stored.
if 'selected_category' in selections:
#Match an available category to the previously selected category.
#If the 'selected_unts' has been stored, then extract self._selected_units from selections.
if 'selected_units' in selections:
self._selected_units = selections['selected_units']
#Make sure that the 'self._selected_category' has been stored.
if 'selected_category' in selections:
#Match an available category to the previously selected category.