When can one use the `is` operator in Python to determine if two objects are the same object as opposed to just having the same value?

Question

I am not asking when to use == vs is in Python which is a question that has been asked and answered many times before.

As stated here, == checks if two arguments have the same value, and is checks if the they refer to the same object.

So if one creates two objects with the same value,

>>> fruit_name = 'Apple'
>>> company_name = 'Apple'

one would expect == to return True and is to return False. However this is what actually happens:

>>> fruit_name == company_name # True expected since they have the same value
True
>>> fruit_name is company_name 
True

Why is Python considering fruit_name and company_name to be the same object as opposed to different objects with the same value? And when can one rely on is to return True if and only if the arguments are intentionally set to be the same object by the programmer?

rely on `is` only for singletons (`None` for instance). Not for strings or integers, that's for sure. — Jean-François Fabre, Sep 21 '17 at 06:57
You got lucky. Sometimes the interpreter reuses the same value across multiple variables. This is true mostly for immutable types. — cs95, Sep 21 '17 at 06:58
See also https://stackoverflow.com/questions/2123925/when-does-python-allocate-new-memory-for-identical-strings — Thierry Lathuille, Sep 21 '17 at 06:59
Also see [About the changing id of an immutable string](//stackoverflow.com/q/24245324) — Martijn Pieters, Sep 21 '17 at 07:00
@Jean-FrançoisFabre I am not asking when to use `is` vs `==` which I already acknowledged as previously answered so this question is not an exact duplicate of the first question you linked to. The 2nd question you linked to is similar but is far more complicated and hard to follow. — Semihcan Doken, Sep 21 '17 at 07:18
who can find a better duplicate than the 2 above? oh Martjin already added that one. — Jean-François Fabre, Sep 21 '17 at 07:30
I found this answer helpful. https://stackoverflow.com/a/1504848/5191836 — Semihcan Doken, Sep 21 '17 at 07:32

When can one use the `is` operator in Python to determine if two objects are the same object as opposed to just having the same value?

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