still have a problem with getting dialogforms to construct_instance()

[amikphoto]

Just updated to 2.1 and when I try to submit formcollections with dialogmodelforms I've got an errors AttributeError: 'AddDishCatalogForm' object has no attribute 'cleaned_data'. Did you mean: 'changed_data'?
It happens in def construct_instance(self, instance=None): of collection.py. It happens because DialogModelFroms trying to get to construct_instance. I fix it with condition if not hasattr(holder, 'cleaned_data'): continue:

def construct_instance(self, instance=None):
    """
    Construct the main instance and all its related objects from the nested dictionary. This
    method may only be called after the current form collection has been validated, usually by
    calling `is_valid`.

    Forms and Collections which do not correspond to the model given by the starting instance,
    are responsible themselves to override this method in order to store the corresponding data
    inside their related models.
    """
    assert self.is_valid(), f"Can not construct instance with invalid collection {self.__class__} object"
    if self.has_many:
        for valid_holders in self.valid_holders:
            # first, handle holders which are forms
            for name, holder in valid_holders.items():
                if not isinstance(holder, BaseModelForm):
                    continue
                if holder.marked_for_removal:
                    holder.instance.delete()
                    continue
                construct_instance(holder, holder.instance)
                if getattr(self, 'related_field', None):
                    setattr(holder.instance, self.related_field, instance)
                try:
                    holder.save()
                except (IntegrityError, ValueError) as error:
                    # some errors are caught only after attempting to save
                    holder._update_errors(error)

            # next, handle holders which are sub-collections
            for name, holder in valid_holders.items():
                if callable(getattr(holder, 'construct_instance', None)):
                    holder.construct_instance(holder.instance)
    else:
        for name, holder in self.valid_holders.items():
            if callable(getattr(holder, 'construct_instance', None)):
                holder.construct_instance(instance)
            elif isinstance(holder, BaseModelForm):
                // This is my condition
                                    if not hasattr(holder, 'cleaned_data'):
                                        continue
                //
                opts = holder._meta
                holder.cleaned_data = self.cleaned_data[name]
                holder.instance = instance
                construct_instance(holder, instance, opts.fields, opts.exclude)
                try:
                    holder.save()
                except IntegrityError as error:
                    holder._update_errors(error)

Is it correct?