diff --git a/modules/aeolus/datasource.py b/modules/aeolus/datasource.py
index 34d28a704508c8397bb94af246b8a54d33538194..8891446845dea2f2f345e47b07e41559f3cba063 100644
--- a/modules/aeolus/datasource.py
+++ b/modules/aeolus/datasource.py
@@ -138,8 +138,9 @@ class Files:
 
     def __next__(self):
         if self._current_index < len(self.flist):
+            fname = self.flist[self._current_index]
             self._current_index += 1
-            return self.flist[self._current_index]
+            return fname
 
         self._current_index = 0
         raise StopIteration