We can call outside defined subroutines from the Safe
compartment using share(), and call methods through the object that is
copied into the Safe compartment using varglob(). However, these
subroutines and methods are still executed in the Safe compartment, so
they cannot call other subroutines that are dynamically qualified with
the package name, such as class methods.

	Through Safe::Hole, we can execute outside defined subroutines
in the original main compartment from the Safe compartment.