diff --git a/main.py b/main.py
index a84f482..5f76716 100644
--- a/main.py
+++ b/main.py
@@ -35,24 +35,24 @@ def reset_joysticks():
             sys.exit()
         if event.type in [pygame.JOYDEVICEADDED, pygame.JOYDEVICEREMOVED]:
             joysticks = reset_joysticks()
-    
+
     window.fill('white')
-    
+
     for joystick in joysticks:
         controller = Controller.from_joystick(joystick)
         js = [joystick.get_guid(), joystick.get_name()]
         for button in range(joystick.get_numbuttons()):
-            btn_message = 'Button ' + str(button) + ': ' + str(controller.get_button(button))
+            btn_message = f'Button {str(button)}: {str(controller.get_button(button))}'
             js.append(btn_message)
         for axis in range(joystick.get_numaxes()):
-            axis_message = 'Axis ' + str(axis) + ': ' + str(controller.get_axis(axis))
+            axis_message = f'Axis {str(axis)}: {str(controller.get_axis(axis))}'
             js.append(axis_message)
         for hat in range(joystick.get_numhats()):
-            hat_message = 'Hat ' + str(hat) + ': ' + str(joystick.get_hat(hat))
+            hat_message = f'Hat {str(hat)}: {str(joystick.get_hat(hat))}'
             js.append(hat_message)
-        
+
         debug_messages.append(js)
-    
+
     for js, dbg_messages in enumerate(debug_messages):
         for i, message in enumerate(dbg_messages):
             l = 20 if js == 0 else js * 420
diff --git a/main_test_.py b/main_test_.py
index 3d48668..2f18d2e 100644
--- a/main_test_.py
+++ b/main_test_.py
@@ -37,13 +37,13 @@ def reset_joysticks():
     for joystick in joysticks:
         js = [joystick.get_guid(), joystick.get_name()]
         for button in range(joystick.get_numbuttons()):
-            btn_message = 'Button ' + str(button) + ': ' + str(joystick.get_button(button))
+            btn_message = f'Button {str(button)}: {str(joystick.get_button(button))}'
             js.append(btn_message)
         for axis in range(joystick.get_numaxes()):
-            axis_message = 'Axis ' + str(axis) + ': ' + str(joystick.get_axis(axis))
+            axis_message = f'Axis {str(axis)}: {str(joystick.get_axis(axis))}'
             js.append(axis_message)
         for hat in range(joystick.get_numhats()):
-            hat_message = 'Hat ' + str(hat) + ': ' + str(joystick.get_hat(hat))
+            hat_message = f'Hat {str(hat)}: {str(joystick.get_hat(hat))}'
             js.append(hat_message)
 
         debug_messages.append(js)