$2\mathrm{.}8.$ Show that the following encryption scheme does not have one$-$time secrecy$,$ by constructing a program that distinguishes the two relevant libraries from the one$-$time secrecy definition.

$\{\begin{array}{ccc}\text{:}C=Z_{10}& \text{r}\text{e}\text{t}\text{u}\text{r}\text{n}& k\end{array}$