python - Difference between not dict and not dict=={} -

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came in today , debugged find there deviation in behaviour predicted result of not adict being treated differently not adict=={}. in know highlight differences between these 2 forms please.

deviation caused on following line of code

if not adicta , not adictb:

both equal {} , yet if condition didn't return true.

line of code changed to

if not adicta=={} , not adictb=={}:

and code worked expected.

you right in thinking empty dictionaries false in boolean context. therefore, not {} , empty_dict == {} equivalent, however...

in first one, checking if false.

>>> not {} true

but in second one, checking if empty (therefore false) , reversing not.

>>> not not {}  # doing. false

you different results because not testing same condition.


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