Library: Port 'Tooltip' to Python (#729)

Author: UrtsiSantsi

src/Library/demos/Tooltip/main.py

@@ -0,0 +1,21 @@
+import gi
+
+gi.require_version("Gtk", "4.0")
+from gi.repository import Gtk
+import workbench
+
+button: Gtk.Button = workbench.builder.get_object("button")
+
+
+def on_query_tooltip(button, x, y, mode, tooltip):
+    custom_tooltip = Gtk.Box(spacing=6)
+    label = Gtk.Label(label="This is a custom tooltip")
+    icon = Gtk.Image(icon_name="penguin-alt-symbolic")
+    custom_tooltip.append(label)
+    custom_tooltip.append(icon)
+
+    tooltip.set_custom(custom_tooltip)
+    return True
+
+
+button.connect("query-tooltip", on_query_tooltip)