Let's say I have created two objects from class foo and now want to combine the two. How, if at all possible, can I accomplish that within a function like this:

def combine(first, second):
    first.value += second.value
    del second #this doesn't work, though first.value *does* get changed

instead of doing something like

def combine(first, second):
    first.value += second.value

in the function and putting del second immediately after the function call?