handle wikidata dagster asset for rki

mex/pipeline/wikidata.py

@@ -1,5 +1,4 @@
-from collections.abc import Generator
-
+from mex.common.exceptions import MExError
 from mex.common.models import ExtractedOrganization, ExtractedPrimarySource
 from mex.common.wikidata.extract import search_organization_by_label
 from mex.common.wikidata.models.organization import WikidataOrganization
@@ -11,21 +10,23 @@
 
 
 @asset(group_name="default")
-def wikidata_organization_rki() -> WikidataOrganization | None:
+def wikidata_organization_rki() -> WikidataOrganization:
     """Extract WikidataOrganization for Robert Koch-Institut."""
-    return search_organization_by_label("Robert Koch-Institut")
+    if org := search_organization_by_label("Robert Koch-Institut"):
+        return org
+    raise MExError("RKI not found on wikidata, cannot proceed.")
 
 
 @asset(group_name="default")
 def extracted_organization_rki(
     wikidata_organization_rki: WikidataOrganization,
     extracted_primary_source_wikidata: ExtractedPrimarySource,
-) -> Generator[ExtractedOrganization, None, None]:
+) -> ExtractedOrganization:
     """Transforms RKI organization data to extracted organizations and load result."""
-    extracted_organization_rki = (
+    extracted_organization_rki = list(
         transform_wikidata_organizations_to_extracted_organizations(
             [wikidata_organization_rki], extracted_primary_source_wikidata
         )
     )
     load(extracted_organization_rki)
-    return extracted_organization_rki
+    return extracted_organization_rki[0]