Unnamed

def foo(initial_value=0):
    varholder = [initial_value]   # put the value into a list
    def var_setter(newval):
        varholder[0] = newval
    def var_getter():
        return varholder[0]
    return var_setter, var_getter

setter, getter = foo()
setter(21)
getter()      # <- would return 21