Let f : X gt; Y be a map between metric Spaces. Prove that if (f @3an n=0 converges in Y whenever (33")310 converges in X then f is continuous....

How do I prove this question about the convergence of sequences implying a function is continuous?

3. Let f : X —> Y be a map between metric Spaces. Prove that if (f @3an n=0 converges in Y whenever (33”)310 converges in X then f is continuous.[Note: it is not given that f (33”) —> f(a:) Whenever sun —> 32.]