public AddressSet getAddressesOnlyInTwo() {
        return new AddressSet(onlyInTwo);
    }
Returns the addresses that are in program2, but not in program1
 The returned address set is derived using program2.
@return the addresses that are in program2, but not in program1.
Ghidra/Features/Base/src/main/java/ghidra/program/util/ProgramMemoryComparator.java