class Person: _fname as string
    _lname as string
    def constructor(fname, lname):
        raise ArgumentNullException("fname") if fname is null
        raise ArgumentNullException("lname") if lname is null
        _fname = fname
         _lname = lname
        FirstName as string:
            get:
                return _fname
        LastName as string:
            get:
                return _lname