Cannot convert to managed type #1900

Environment

• Pythonnet version: 3.0.0-rc4
• Python version: 3.8
• Operating System: Windows11
• .NET Runtime: .NET Framework 4.8

Details

With the following code in C#, when a Python class has getitem() defined, it will be converted to an array (System.Object[]) in managed code:

List lst = new List();
using (Py.GIL())
{
using (var scope = Py.CreateScope())
{
scope.Set("lst", lst);
string text = @"
class DBRow:
def init(self, row, col_names):
self.row = row
self.col_names = col_names

def __getitem__(self, key):   
    if isinstance(key, int):
        return self.row[key]

    if key in self.col_names:
        index = self.col_names.index(key)
        return self.row[index]
    else:
        return None 

col_names=['col1', 'col2', 'col3']
row=[1, '2', 3]

r = DBRow(row, col_names)
lst.Add(r)
";

                    var code = PythonEngine.Compile(text);
                    scope.Execute(code);
                }
            }
            string str = lst[0].GetType().ToString();