[IshKebab]

You should do normally do

    data = collection.get("key")
    if data is not None:
         ...
    else:
         ....

[japhyr]

Wouldn't this be a little cleaner?

    data = collection.get("key")
    if data:
        ...
    else:
        ...

[pansa2]

If valid `data` can be zero, an empty string, or anything else “falsy”, then your version won’t handle those values correctly. It treats them the same as `None`, i.e. not found.

[japhyr]

:facepalm:

[blackbear_]

No, this would crash with numpy arrays, pandas series and such, with a ValueError: The truth value of an array with more than one element is ambiguous.

[IshKebab]

No, truthiness (implicit bool coercion) is another thing you should avoid. This will do weird things if data is a string or a list or whatever.

[Shish2k]

That behaves differently (eg if collection["key"] = 0)

[tayo42]

it depends on what's in the if blocks

[echoangle]

The value in the collection could be the actual value None, that’s different from the collection not having the key.

[eesmith]

    missing = object()
    data = collection.get("key", missing)
    if data is missing:
         ...
    else:
         ....

[IshKebab]

That's why I said "normally".