All bulk_update() objects must have a primary key set.

Raise code

""" 
        """
        if batch_size is not None and batch_size < 0:
            raise ValueError('Batch size must be a positive integer.')
        if not fields:
            raise ValueError('Field names must be given to bulk_update().')
        objs = tuple(objs)
        if any(obj.pk is None for obj in objs):
            raise ValueError('All bulk_update() objects must have a primary key set.')
        fields = [self.model._meta.get_field(name) for name in fields]
        if any(not f.concrete or f.many_to_many for f in fields):
            raise ValueError('bulk_update() can only be used with concrete fields.')
        if any(f.primary_key for f in fields):
            raise ValueError('bulk_update() cannot be used with primary key fields.')
        if not objs:
            return