WeakrefValueDictionary of Callables?

[Lloyd Weehuizen]

Hey

I'm trying to set up a WeakrefValueDictionary of callables however as 
soon as my method that adds the callable to the dictionary exits the 
value is removed? Is there any way around this?

Example:
import weakref
TEST_EVENT = 1

class TestBinder:
	def __init__( self ):
		self.entries = weakref.WeakValueDictionary()
		
	def BindFunction( self, event_id, function ):
		self.entries[event_id] = function

	def CallFunction( self, event_id, *args ):
		self.entries[event_id]( *args )


class TestCase:
	def __init__( self, binder ):
		binder.BindFunction( TEST_EVENT, self.TestFunction )
		
	def TestFunction():
		print "TestFunction OK"

test_binder = TestBinder()
test_case = TestCase( test_binder )

test_binder.CallFunction( TEST_EVENT )

This generates a KeyError: 1, if I don't use weakrefs, then the TestCase 
object is never cleaned up until TestBinder is destroyed.

Thanks