def __getitem__(self, field_name):
		field = self.instance._meta._forward_fields_map[field_name]
		
		try:
			if field.attname not in self.instance._changed_fields:
				return getattr(self.instance, field.name)
			
			elif self.instance._changed_fields in field.name:
				return self.instance._changed_fields[field.name]
			
			elif field.is_relation and self.instance._changed_fields[field.attname] is not None:
				try:
					self.instance._changed_fields[field.name] = getattr(
						self.instance.__class__,
						field.name
					).get_queryset().get(pk=self.instance._changed_fields[field.attname])
				
				except self.instance.DoesNotExist:
					self.instance._changed_fields[field.name] = DoesNotExist
			
			else:
				return self.instance._changed_fields[field.attname]
		
		except (AttributeError, KeyError):
			raise KeyError(field_name)
dataset/ETHPy150Open karanlyons/django-save-the-change/save_the_change/mixins.py/OldValues.__getitem__/swapped operands of `in`