Optimize attribute lookup in DSMR Reader

[erwindouna]

Breaking change

Proposed change

Optimize attribute lookups, by introducing the walrus operator. Should save a few lookups.

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• This PR fixes or closes issue: fixes #
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[home-assistant]

Hey there @sorted-bits, @Glodenox, mind taking a look at this pull request as it has been labeled with an integration (dsmr_reader) you are listed as a code owner for? Thanks!

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[Glodenox]

I might be wrong due to my somewhat limited knowledge of Python, but I think this will have the unwanted effect of marking zeros and False values as None.

[erwindouna]

That's a sharp observation! I didn't take the actual 0 in consideration. I can write a fix for it.

[erwindouna]

While digging into it, I found that the payload is always either a str or bytes:

So that means all non-empty values (0 and False) are handled truthfully. I believe the optimization is safe. :)

[Glodenox]

Ah, then there's no risk indeed :)