human
I wrote the below code

    (models, multiple) = datastore.NormalizeAndTypeCheck(models, Model)
    entities = [model._populate_internal_entity() for model in models]
    def extra_hook(keys):
        if multiple:
            return keys
        assert (len(keys) == 1)
        return keys[0]
    return datastore.PutAsync(entities, extra_hook=extra_hook, **kwargs)

What's a good function header?
assistant
#Here's a good function header.

def put_async(models, **kwargs):