Question

Is it possible to get the keys that where changed when using the update method?

def func(**kw):
    d = {'key0' : 0, 'key1' : 1}
    d.update(**kw)

func(kw0=0, kw1=1)

In the above code I’d want to get the keys ‘kw0’ and ‘kw1’.

Answer 1

No, once update() is called, they are indistinguishable from the other keys.

Inside the function you can still look at kw.keys() to see which ones were passed in

eg

def func(**kw):
    d = {'key0' : 0, 'key1' : 1}
    d.update(**kw)
    print "updated %s"%kw.keys()

func(kw0=0, kw1=1)