debugging session modality identification

xnat_ingest/session.py

@@ -91,7 +91,7 @@ def make_session_id(cls, project_id, subject_id, visit_id):
     def modalities(self) -> ty.Set[str]:
         modalities = self["Modality"]
         if not isinstance(modalities, str):
-            modalities = set(tuple(m) if not isinstance(str) else m for m in modalities)
+            modalities = set(tuple(m) if not isinstance(m, str) else m for m in modalities)
         return modalities
 
     @property