diff --git a/unittests/test_scanner.py b/unittests/test_scanner.py
index 6aa7287b2449f49706cb352d24fa8abf66f87115..1233370d02f94ed5aa0fb39612774b7b0524e54c 100644
--- a/unittests/test_scanner.py
+++ b/unittests/test_scanner.py
@@ -1,34 +1,46 @@
+#!/usr/bin/env python3
+# encoding: utf-8
+#
+# This file is a part of the CaosDB Project.
+#
+# Copyright (C) 2023 Indiscale GmbH <info@indiscale.com>
+# Copyright (C) 2023 Henrik tom Wörden <h.tomwoerden@indiscale.com>
+#               2023 Research Group Biomedical Physics,
+# Max-Planck-Institute for Dynamics and Self-Organization Göttingen
+# Alexander Schlemmer <alexander.schlemmer@ds.mpg.de>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <https://www.gnu.org/licenses/>.
+#
+
+"""
+Unit test functions for the scanner.
+"""
 
-import json
-import logging
-import os
-import warnings
-from copy import deepcopy
 from functools import partial
-from os.path import basename, dirname, join
 from pathlib import Path
 from tempfile import NamedTemporaryFile
 from unittest.mock import MagicMock, Mock, patch
 
 import caosdb as db
-import caosdb.common.models as dbmodels
 import pytest
 import yaml
-from caoscrawler.crawl import (Crawler, SecurityMode, _treat_deprecated_prefix,
-                               crawler_main, split_restricted_path)
+from caoscrawler.crawl import Crawler
 from caoscrawler.debug_tree import DebugTree
-from caoscrawler.identifiable import Identifiable
-from caoscrawler.identifiable_adapters import (CaosDBIdentifiableAdapter,
-                                               IdentifiableAdapter,
-                                               LocalStorageIdentifiableAdapter)
 from caoscrawler.scanner import (create_converter_registry, load_definition,
                                  scan_directory, scan_structure_elements)
-from caoscrawler.stores import GeneralStore, RecordStore
 from caoscrawler.structure_elements import (DictElement, DictListElement,
                                             DictTextElement, File)
-from caosdb.apiutils import compare_entities
-from caosdb.cached import cache_clear
-from caosdb.exceptions import EmptyUniqueQueryError
 from pytest import raises
 
 from utils import dircheckstr as dircheck_base