Serving a term of imprisonment, at least when it is not of trivial duration, is something out of the ordinary. Of course it does not mean that a person in prison in any given jurisdiction is never to be regarded as ordinarily resident in that jurisdiction for any purpose. Certainly I would not be disposed to hold, for example, that the fact of being in prison somewhere would of itself render a person not ordinarily resident there when his being so would render him liable to tax.