human
Complete this python program:
def get_async(keys, **kwargs):
assistant
#Here is the Python code you requested.

    """Asynchronously fetch the specified Model instance(s) from the datastore.
    Identical to db.get() except returns an asynchronous object. Call
    get_result() on the return value to block on the call and get the results.
    """
    (keys, multiple) = datastore.NormalizeAndTypeCheckKeys(keys)
    def extra_hook(entities):
        if ((not multiple) and (not entities)):
            return None
        models = []
        for entity in entities:
            if (entity is None):
                model = None
            else:
                cls1 = class_for_kind(entity.kind())
                model = cls1.from_entity(entity)
            models.append(model)
        if multiple:
            return models
        assert (len(models) == 1)
        return models[0]
    return datastore.GetAsync(keys, extra_hook=extra_hook, **kwargs)