Move make_icon func to MedTrackerApp class

src/main.py

@@ -48,8 +48,7 @@ class MedTrackerApp:
                     f" Using default file: {self.filename}"
                 )
 
-        make_icon(
-            app=self.root,
+        self.make_icon(
             img="/home/will/Code/thechart/chart-671.png",
             logger=logger,
         )
@@ -595,18 +594,17 @@ class MedTrackerApp:
             self.fig.autofmt_xdate()
         self.canvas.draw()
 
-
-def make_icon(app: tk.Tk, img: str, logger: logging.Logger) -> None:
-    try:
-        icon_image = Image.open(img)
-        icon_image = icon_image.resize(
-            size=(32, 32), resample=Image.Resampling.NEAREST
-        )
-        icon_photo = ImageTk.PhotoImage(image=icon_image)
-        app.iconphoto(True, icon_photo)
-        app.wm_iconphoto(True, icon_photo)
-    except FileNotFoundError:
-        logger.warning("Icon file not found.")
+    def make_icon(self, img: str, logger: logging.Logger) -> None:
+        try:
+            icon_image = Image.open(img)
+            icon_image = icon_image.resize(
+                size=(32, 32), resample=Image.Resampling.NEAREST
+            )
+            icon_photo = ImageTk.PhotoImage(image=icon_image)
+            self.root.iconphoto(True, icon_photo)
+            self.root.wm_iconphoto(True, icon_photo)
+        except FileNotFoundError:
+            logger.warning("Icon file not found.")
 
 
 if __name__ == "__main__":