[IronPython] def within a def

[Artie Ziff]

Hi,

Apologies if this is actually a general python inquiry. Due to the
dotnet statement related to adding a handler for an event, I will ask here.

Looking at the examples on the "IronPython & Windows Forms" page, I see
a code that I am not familiar. In the 2nd example on this page,
<http://www.voidspace.org.uk/ironpython/winforms/part5.shtml>, I am
unfamiliar with placing a method (in this case "update") inside a
constructor.

I see that the method "update" is being added to the button's event
handler in the constructor, __init__. Why must this method be defined
inside the constructor? Is there a name for this? Is this an example of
a PEP 309, Partial Function Application?

Cheers,
Art