Getting back Elements ids after running python!

If I run a python script to a list of elements to get acceptable and unacceptable as outputs. Is there a way i can get back element ids of acceptable and unacceptable elements separately? I got the list of all the ids. Just need them sorted as two lists; acceptable ones and unacceptable ones!!

try list comprehension

Acceptable = [c for c in a if c >0.75]
Unacceptable = [c for c in a if c <0.75]

OUT = Acceptable,Unacceptable