diff --git a/src/caosadvancedtools/cfood.py b/src/caosadvancedtools/cfood.py
index 6142e68c0989584b46c3e1294ed2faabbb3f0b10..1bfb7c39ab7da7931906e698911c6123d18d35c1 100644
--- a/src/caosadvancedtools/cfood.py
+++ b/src/caosadvancedtools/cfood.py
@@ -66,11 +66,14 @@ def get_entity(name):
 
 
 class FileGuide(object):
-    def access(path):
+    def access(self, path):
         """ should be replaced by a function that adds
-        a prefix to paths to allow to access caosdb files locally"""
+        a prefix to paths to allow to access caosdb files locally
 
-        raise NotImplementedError()
+        This default just returns the unchanged path.
+        """
+
+        return path
 
 
 fileguide = FileGuide()