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From: ram@zedat.fu-berlin.de (Stefan Ram)
Newsgroups: comp.lang.python
Subject: Re: If a dictionary key has a Python list as its value!
Date: 7 Mar 2024 19:21:31 GMT
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Varuna Seneviratna <varunaseneviratna@gmail.com> wrote or quoted:
>If a dictionary key has a Python list as its value, you can read the values
>one by one in the list using a for-loop like in the following.
>d = {k: [1,2,3]}
>> for v in d[k]:
>>      print(v)
>No tutorial describes this, why?
>What is the Python explanation for this behaviour?

  This is explained by extensionality: To find the behavior of 
  "for v in ...", the only thing one needs to know about "..."
  is its value. You could just as well have written:

l = d[ k ]
for v in l:

  . l can be any iterable. It does not matter where it came from.
  It does not matter that it cam from a dictionary. There are thousand
  places where it could have come from, and no tutorial can name them
  all.