diff --git a/nwp/assets/cams/cams.py b/nwp/assets/cams/cams.py
index fb2c0dd..c5dd824 100644
--- a/nwp/assets/cams/cams.py
+++ b/nwp/assets/cams/cams.py
@@ -2,7 +2,7 @@
 
 import cdsapi
 import dagster
-
+from dagster import AssetObservation
 
 VARIABLES: list[str] = [
             'aerosol_extinction_coefficient_1064nm', 'aerosol_extinction_coefficient_355nm', 'aerosol_extinction_coefficient_532nm',