diff --git a/app/class_media_file_stat.py b/app/class_media_file_stat.py
index 288be56..9e6440b 100755
--- a/app/class_media_file_stat.py
+++ b/app/class_media_file_stat.py
@@ -1,27 +1,47 @@
 import logging
+from typing import TYPE_CHECKING
 
 import yaml
 import os
 
+if TYPE_CHECKING:
+    from app.class_media_file import Media
+
 class Stat:
-    def __init__(self):
+    """
+    Handles reading and writing video conversion statistics
+    """
+
+    def __init__(self) -> None:
+        """
+        Initialize Class with path for statistic file
+        """
         self.path = "app/cfg/statistic.yaml"
 
-    def save_stat(self, obj):
+    def save_stat(self, obj: "Media") -> None:
+        """
+        Saves the statistic in YAML file
+        :param obj: Media object
+        :type obj: Media
+        """
 
         daten = self.read_stat()
 
-        # Neuen Eintrag hinzufügen
-        daten["videos"].update(obj.to_dict_stat())
-
-        # Datei mit aktualisierten Daten speichern
         try:
+            # Neuen Eintrag hinzufügen
+            daten["videos"].update(obj.to_dict_stat())
+
             with open(self.path, "w", encoding="utf8") as file:
                 yaml.dump(daten, file, default_flow_style=False, indent=4, allow_unicode=True)
         except Exception as e:
             logging.error(f"Save Stat Failure: {e}")
 
-    def read_stat(self):
+    def read_stat(self) -> Dict[str, any]:
+        """
+        Read statistic from YAML file
+        :return: Dictionary width statistics
+        :rtype: Dict[str, any]
+        """
         # Bestehende Daten laden
         if os.path.exists(self.path):
             with open(self.path, "r", encoding="utf8") as file:
diff --git a/client/icons/close-144.png b/client/icons/close-144.png
old mode 100644
new mode 100755
diff --git a/client/icons/stat-100.png b/client/icons/stat-100.png
old mode 100644
new mode 100755