fromrest_frameworkimportserializersclassBar(serializers.Serializer):a=serializers.ListSerializer(child=serializers.IntegerField(allow_null=True)    )classFoo(serializers.Serializer):a=serializers.IntegerField(allow_null=True)b=Bar()foo=Foo(data={'a':1,'b': {'a': [None]}})print(foo.is_valid(raise_exception=True))# this passesprint(foo.data)# this triggers the error

File~/workspace/django-rest-framework/rest_framework/serializers.py:714,in<listcomp>(.0)709# Dealing with nested relationships, data can be a Manager,710# so, first get a queryset from the Manager if needed711iterable=data.all()ifisinstance(data,models.manager.BaseManager)elsedata713return [-->714self.child.to_representation(item)foriteminiterable715 ]File~/workspace/django-rest-framework/rest_framework/fields.py:923,inIntegerField.to_representation(self,value)922defto_representation(self,value):-->923returnint(value)TypeError:int()argumentmustbeastring,abytes-likeobjectoranumber,not'NoneType'