assistant: ```xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE interface>
<interface>
  <requires lib="gtk+" version="3.0"/>
  <object class="GtkWindow" id="main_window">
    <property name="title">To-Do List</property>
    <property name="default-width">600</property>
    <property name="default-height">400</property>
    <child>
      <object class="GtkBox">
        <property name="orientation">vertical</property>
        <property name="spacing">10</property>
        <child>
          <object class="GtkGrid">
            <property name="column-homogeneous">TRUE</property>
            <property name="row-spacing">6</property>
            <property name="column-spacing">6</property>
            <property name="margin-start">10</property>
            <property name="margin-end">10</property>
            <property name="margin-top">10</property>
            <property name="margin-bottom">10</property>
            <child>
              <object class="GtkLabel">
                <property name="label">Task:</property>
              </object>
              <packing>
                <property name="left-attach">0</property>
                <property name="top-attach">0</property>
              </packing>
            </child>
            <child>
              <object class="GtkEntry" id="task_entry"/>
              <packing>
                <property name="left-attach">1</property>
                <property name="top-attach">0</property>
              </packing>
            </child>
            <child>
              <object class="GtkLabel">
                <property name="label">Due Date:</property>
              </object>
              <packing>
                <property name="left-attach">0</property>
                <property name="top-attach">1</property>
              </packing>
            </child>
            <child>
              <object class="GtkEntry" id="due_date_entry"/>
              <packing>
                <property name="left-attach">1</property>
                <property name="top-attach">1</property>
              </packing>
            </child>
            <child>
              <object class="GtkButton">
                <property name="label">Add Task</property>
                <property name="expand">FALSE</property>
                <property name="halign">end</property>
                <property name="valign">end</property>
                <signal name="clicked" handler="on_add_task_button_clicked"/>
              </object>
              <packing>
                <property name="left-attach">1</property>
                <property name="top-attach">2</property>
              </packing>
            </child>
          </object>
        </child>
        <child>
          <object class="GtkScrolledWindow">
            <property name="hscrollbar-policy">never</property>
            <property name="vscrollbar-policy">always</property>
            <child>
              <object class="GtkListBox" id="task_list"/>
            </child>
          </object>
        </child>
      </object>
    </child>
  </object>
</interface>
```


This XML code defines a GTK window for a To-Do list application that follows Gnome's design guidelines. The window contains a vertical box with a grid for adding tasks and a scrolled list box for displaying existing tasks. The grid contains labels and text entries for the task name and due date, as well as a button to add the task to the list. The list box displays the tasks in a scrollable list. The code also includes signal handlers for the add task button's "clicked

prompter: Can you write some C# code to create a window and load that interface into it?

assistant: To create a GTK window in C# and load the provided XML interface, you'll need to use the GtkSharp library. 
Make sure to install the required NuGet packages for GtkSharp (Gtk3 and Gdk3), then you can use the following code:

```csharp
using System;
using Gtk;
using UI = Gtk.Builder.ObjectAttribute;

public class TodoListApp : Application
{
    [UI] private ApplicationWindow mainWindow = null;

    public TodoListApp() : base("org.example.TodoListApp", ApplicationFlags.None) { }

    protected override void OnActivate()
    {
        base.OnActivate();
        var builder = new Builder();
        builder.AddFromString(xmlInterface);
        builder.Autoconnect(this);
        mainWindow.ShowAll();
    }

    private static string xmlInterface = @"<!-- The XML string containing your UI design -->";

    public static void Main(string[] args)
    {
        Application.Init();
        var app = new TodoListApp();
        app.Run(args);
    }
}
```

Replace <!-- The XML string containing your UI design --> with the XML string containing the UI design you provided earlier.
This code defines a TodoListApp class that inherits from the Gtk.Application class. The OnActivate method is overridden to load the provided XML interface using the Gtk.Builder class. The Autoconnect method is used to connect the C# class members with the corresponding widgets in the XML.
Remember to install the GtkSharp NuGet packages before running the code.