diff --git a/find_duplicate_files/find_duplicate_files.py b/find_duplicate_files/find_duplicate_files.py
index 537f657..f57b892 100644
--- a/find_duplicate_files/find_duplicate_files.py
+++ b/find_duplicate_files/find_duplicate_files.py
@@ -56,7 +56,7 @@ class find_duplicate_files:
                             ignore_hidden_files=ignore_hidden_files
                         )
                         if more_files:
-                            files = files + more_files
+                            files = { **files, **more_files }
         except PermissionError as error:
             self._log.warning(f"Permission denied accessing folder '{path}'")
         return files