Overrides drop-down list

I give up ... can someone tell me where to find the OVERRIDES drop-down list that the Msdn.Microsoft.com site talks about?

Creating the Derived DataGridTextBoxColumn
The next step is to add the class code for the derived DataGridTextBoxColumn. This is done in the same way, right-clicking the project in Solution Explorer and adding a new class named FormattableTextBoxColumn. To add the stub for the Paint override, select (Overrides) in the left drop-down list on top of the editing window,