Set default KMS encryption key for objects in the bucket.

        :type value: str or None
        :param value: new KMS key name (None to clear any existing key).

def default_kms_key_name(self, value):
        """Set default KMS encryption key for objects in the bucket.

        :type value: str or None
        :param value: new KMS key name (None to clear any existing key).
        """
        encryption_config = self._properties.get("encryption", {})
        encryption_config["defaultKmsKeyName"] = value
        self._patch_property("encryption", encryption_config)