It is a Night snake ( Hypsiglena torquata deserticola), apparently they get a little larger in their northern range (20"), they are on the Redlist in Canada and listed as threatened in Texas and AZ., They eat small rorents, frogs, lizards, and insects. They are very mellow snakes that hand tame easily even if their venom feels like a wasp sting. I had one years ago but gave it to the wildlife display at Ft. Sam Houston, Texas.
I'll post something different.
Here is one you would be foolish to keep, it is a man killer and not native to the Americas.