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Comment by IshKebab | Hacker News Reader

You should do normally do

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

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Wouldn't this be a little cleaner?

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

it depends on what's in the if blocks

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

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.

:facepalm:

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.

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.

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

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

That's why I said "normally".

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