Prove axiom of infinity from ZF$-$Infinity +Zermelo's version of infinity

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Assume ZF-infinity and assume that there is a set $X$ such that $\varnothing\in X$ and for all $t\in X$, $\{t\}\in X$. How to deduce axiom of infinity from these new axioms?

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Hint: By replacement, $Y = \{ \operatorname{rank}_{\in}(x) \mid x \in X\}$ is a set and it's now easy to check that $\omega \subseteq Y$.