diff --git a/src/gisaf/baskets.py b/src/gisaf/baskets.py
index 0c377be..5adffc8 100644
--- a/src/gisaf/baskets.py
+++ b/src/gisaf/baskets.py
@@ -38,7 +38,7 @@ class Basket:
     who don't have that role.
     """
     name: ClassVar[str]
-    importer_class: Type[Importer]
+    importer_class: Type[Importer] | None = None
     importer: Importer
     _custom_module: str | None = None
     columns: list[str] = ['name', 'time', 'import', 'delete']
@@ -47,7 +47,7 @@ class Basket:
 
     def __init__(self):
         self.base_dir = Path(conf.admin.basket.base_dir) / self.name
-        if self.importer_class:
+        if self.importer_class is not None:
             self.importer = self.importer_class()
             self.importer.basket = self
 
diff --git a/src/gisaf/importers.py b/src/gisaf/importers.py
index d9e63e1..7d949e3 100644
--- a/src/gisaf/importers.py
+++ b/src/gisaf/importers.py
@@ -1,6 +1,7 @@
 import datetime
 import logging
 import re
+from typing import Any
 from collections import defaultdict, OrderedDict
 from math import isnan
 from mimetypes import guess_type
@@ -39,7 +40,7 @@ class Importer:
     The main process is executed by do_import(file)
     Subclasses should define read_file and process_df.
     """
-    basket = None # type hint: baskets.Basket
+    basket: Any = None # type hint: baskets.Basket
 
     async def do_import(self, file_record, dry_run=False, **kwargs) -> BasketImportResult:
         """