Loop Condition Question

[malonn]

I want to iterate over a loop until an OSError is thrown. That's it. What's the best way to do that. What I'm doing is using winreg.EnumKey to make a list of all sub-keys of a key. The function returns one key at a time. So, I need to loop it, increasing the index each time to enum all keys. How do I stop the loop at an OSError (which is what the docs recommend)?
Just to show some code (this is not how I want to do it)

i = 0
while i < 5:
    list = winreg.EnumKey(<key>, i)
    i += 1

I want something like

while not OSError:
    ....

But my limited understanding is causing errors.

Help is, as always, much appreciated.
malonn