[Python] Complex DataBinding accepts as a data source either an IList or an IListSource....

I'm a hobbyist developer writing python code scripts inside CAD software (to help design and build RC model aircraft). I recently upgraded the CAD software I use and in doing so, it upgraded the version of python from 2.7(Iron Python) to 3.9.10 (.NET Python). This conversion has introduced an issue in my code that I have not been able to find a resolution to.

Put simply, I created a small user interface dialog using Windows.System.Forms components and try to assign values to a ListBox (using the DataSource property). Whilst it worked correctly in python 2.7, it produces an error in 3.9.10 as per the follow message -

Complex DataBinding accepts as a data source either an IList or an IListSource. (Parameter 'value')

An example of the code that generates this error is below:

#! python 3

import clr
clr.AddReference("System.Windows.Forms")
clr.AddReference("System.Drawing")

from System.Windows.Forms import Application, Form, ListBox
from System.Drawing import Point, Size

# Define a simple class
class Fruit:
def __init__(self, name, color):
self.Name = name # Property to display
self.Color = color

def __repr__(self):
return f"{self.Name} ({self.Color})" # For debugging

class MyForm(Form):
def __init__(self):

super().__init__()
self.Text = "ListBox DataSource Example"
self.Size = Size(300, 200)

# Create a ListBox
self.listbox = ListBox()
self.listbox.Location = Point(20, 20)
self.listbox.Size = Size(200, 100)

# Create a list of objects
fruits = [
Fruit("Apple", "Red"),
Fruit("Banana", "Yellow"),
Fruit("Cherry", "Red"),
Fruit("Date", "Brown")
]

# Bind the ListBox to the list of objects
self.listbox.DataSource = fruits
self.listbox.DisplayMember = "Name" # Show the "Name" property

# Add ListBox to form
self.Controls.Add(self.listbox)

# Run the application
form = MyForm()
Application.Run(form)


If anyone can provide a solution to this problem it would be GREATLY appreciated. Many Thanks in Advance.

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