how to show that this complex series converge?

If $$\sum_{n=1}^{\infty} \frac{a_{n}}{n^{s}}$$ Converges( s is real)

and $\operatorname{Re}(z)>s$.
Then $$\sum_{n=1}^{\infty} \frac{a_{n}}{n^{z}}$$
also converges. $a_n$ is complex sequence.