About this 3D model

The same thing as my sinusoidal solid (http://www.thingiverse.com/thing:246134), though this time confined to a sphere. The object is HOLLOW, the third image shows an inside view of the object. The object is solid wherever (abs(cos(2x)+cos(2y)+cos(2z)) < 0.45) && (6 < sqrt(x*x+y*y+z*z) < 9) is true.