Formatted the PyGTK code in README.md as Ruff would.

Except for the imports. The way PyGTK has to be imported is inherently incompatible with the recommendation specified in PEP8 (the Python style guide).

README.md

@@ -73,12 +73,13 @@ Add widgets to the `area` attribute of a `ScrollableAreaQt5`/`ScrollableAreaQt6`
 In GTK, containers are widgets, so they can be aligned in other containers.
 
 ```Python
-import gi; gi.require_version('Gtk', '3.0')
-import gi.repository.Gtk as Gtk
 import itertools
 
+import gi; gi.require_version("Gtk", "3.0")
+from gi.repository import Gtk
+
 window = Gtk.Window()
-window.connect('destroy', Gtk.main_quit)
+window.connect("destroy", Gtk.main_quit)
 window.set_default_size(256, 128)
 
 scrolled_window = Gtk.ScrolledWindow()
@@ -91,9 +92,9 @@ grid.set_column_spacing(20)
 scrolled_window.add(grid)
 
 dim = 10
-for (i, j) in itertools.product(range(dim), repeat=2):
+for i, j in itertools.product(range(dim), repeat=2):
     label = Gtk.Label()
-    label.set_label(f'Label\n({i}, {j})')
+    label.set_label(f"Label\n({i}, {j})")
     grid.attach(label, j, i, 1, 1)
 
 window.show_all()