from itertools import groupby from django import forms from django . forms . models import ModelChoiceIterator , ModelMultipleChoiceField from . models import Feature , Widget class GroupedModelMultipleChoiceField ( ModelMultipleChoiceField ): def __init__ ( self , group_by_field , group_label = None , * args , ** kwargs ): """ ``group_by_field`` is the name of a field on the model ``group_label`` is a function to return a label for each choice group """ super ( GroupedModelMultipleChoiceField , self ). __init__ (* args , ** kwargs ) self . group_by_field = group_by_field if group_label is None : self . group_label = lambda group : group else : self . group_label = group_label def _get_choices ( self ): if hasattr ( self , '_choices' ): return self . _choices return GroupedModelCho