regions – Moment Of Inertia of half cylinder

With cylinder I have:

 body = Cylinder({{-l/2, 0, 0}, {l/2, 0, 0}}, r);
 ((ScriptCapitalI) = (Rho) MomentOfInertia(body, 
 Assumptions -> l > 0 && w > 0 && h > 0)) // MatrixForm; 
 m Cancel((ScriptCapitalI)/((Rho) Volume(body))) // MatrixForm(*Code from MMA help*)

 (*{{(m*r^2)/2, 0, 0}, {0, (m*(l^2 + 3*r^2))/12, 0}, {0, 0, (m*(l^2 + 3*r^2))/12}}*)

But how do this with half cylinder?
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