Change BindableProperty.Create to BindableProperty.Create()

Forum post Change BindableProperty.Create() to BindableProperty.Create()
I looked at above solution, but I can't find a way to change this.

public static BindableProperty itemsSourceProperty =
BindableProperty.Create<BindablePicker, IList>(o => o.ItemsSource, default(IList), propertyChanged: OnItemSourceChanged);

I tried this but i get an error on OnItemSourceChanged

public static BindableProperty itemsSourceProperty =
BindableProperty.Create(nameof(ItemsSource), typeof(IList), typeof(BindablePicker), propertyChanged: OnItemSourceChanged);

Thanks for any help.