def _unique_objects(array, key_properties):
    """
    Test whether objects in an array are unique with respect to the given set of properties.
    """
    key_objects = []
    for obj in array:
        key_object = {k: v for k, v in obj.iteritems() if k in key_properties}
        if key_object in key_objects:
            return False
        key_objects += [key_object]
    return True