[scanFactory] simplify reading

tomoscan/scanfactory.py

@@ -54,8 +54,8 @@ class ScanFactory:
             return EDFTomoScan(scan=scan_path)
         elif HDF5TomoScan.is_tomoscan_dir(scan_path):
             return HDF5TomoScan(scan=scan_path)
-
-        raise ValueError('%s is not a valid scan path' % scan_path)
+        else:
+            raise ValueError('%s is not a valid scan path' % scan_path)
 
     @staticmethod
     def create_scan_objects(scan_path: str) -> tuple: