> restart:

> with (plottools):

> a1:=sphere([1,1,1],1):

> a2:=sphere([1,1,-1],1):

> a3:=sphere([1,-1,1],1):

> a4:=sphere([1,-1,-1],1):

> a5:=sphere([-1,1,1],1):

> a6:=sphere([-1,1,-1],1):

> a7:=sphere([-1,-1,1],1):

> a8:=sphere([-1,-1,-1],1):

> with (plots):

Warning, the name changecoords has been redefined

> display (a1,a2,a3,a4,a5,a6,a7,a8,scaling=constrained);