Temperments can vary. There is no 'standard' temperment I know of to judge against.
Dumerils usually top out at about 7 feet or so but I have a female that is close to 9 - only one I have seen.
In my experience, they can range from being completely docile to having the temperment of a blood python.. aka 'face snatcher' lol
then again, that is just my opinion.
I'm sure many will tell you about their dumeril being the sweatest boa they've ever had the pleasure of dealing with, and some may say they are the devil incarnate.. lol
Some things that matter is who/how they are produced, and if and how they have been and will be handled.
Hope this helped. thanks, Joe
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'Tis not the stongest of the species that will eventually survive, nor the most intelligent, but the one most responsive to change' Charles Darwin
Thanks and take care - Joe Rollo