Organizing modules and their code

[Thomas Passin]

On 2/4/2023 12:24 AM, dn via Python-list wrote:
> The transform is likely dictated by your client's specification. So, 
> another separation. Hence Design 1.
> 
> There is a strong argument for suggesting that we're going out of our 
> way to imagine problems or future-changes (which may never happen). If 
> this is (definitely?) a one-off, then why-bother? If permanence is 
> likely, (so many 'temporary' solutions end-up lasting years!) then 
> re-use can?should be considered.

With practice, it gets to be more automatic to set things up from the 
beginning to more-or-less honor separation of concerns, decoupled 
modules and APIs, and so forth.  Doing this does not require a full, 
future-proof suite of alternative database adapters, for example, right 
from the start. On top of everything else, you can't know the future 
perfectly.  And you can't know enough at the beginning to get every 
design and architectural path optimal. You learn as you go.

I have a Tomcat application where I separated the output formatting from 
the calculation of results.  At the time I wrote only an XML formatter. 
A decade later, here comes JSON, and customers are asking about it.  I 
was able to write a JSON formatter with the same API in about half an 
hour, and now we have optional JSON output. Separating out the 
formatting functionality with its own API was not an example of wasting 
time with YAGNI (You Aren't Going To Need It), it was just plain good 
practice that probably didn't even cost me any more development time - 
since it simplified the calculation code.

OTOH, you may be just trying to learn how to do the bits and pieces. You 
may be learning how to connect to the database. You may be learning how 
to make a pipeline multithreaded.  You have to experiment a thousand 
ways, and in a hurry.  Until you learn how to do the basic techniques, 
sure, quick and dirty is fine.  But it shouldn't be the way you design 
your actual product, unless it's just for you and needs to be done 
quickly, and will probably be ephemeral.

Why do I get the feeling that the OP was asking about a homework problem?