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airflow/models/xcom_arg.py

@@ -370,7 +370,7 @@ def resolve(self, context: Context, session: Session = NEW_SESSION) -> Any:
             return result
         if self.key == XCOM_RETURN_KEY:
             return None
-        if self.operator.multiple_outputs:  # type: ignore
+        if getattr(self.operator, "multiple_outputs", False):
             # If the operator is set to have multiple outputs and it was not executed,
             # we should return "None" instead of showing an error. This is because when
             # multiple outputs XComs are created, the XCom keys associated with them will have