more on python type hint

daemon/core/gui/dialogs/mobilityconfig.py

@@ -2,6 +2,7 @@
 mobility configuration
 """
 from tkinter import ttk
+from typing import TYPE_CHECKING
 
 import grpc
 
@@ -10,9 +11,13 @@ from core.gui.errors import show_grpc_error
 from core.gui.themes import PADX, PADY
 from core.gui.widgets import ConfigFrame
 
+if TYPE_CHECKING:
+    from core.gui.app import Application
+    from core.gui.graph.node import CanvasNode
+
 
 class MobilityConfigDialog(Dialog):
-    def __init__(self, master, app, canvas_node):
+    def __init__(self, master, app: "Application", canvas_node: "CanvasNode"):
         super().__init__(
             master,
             app,