# Question about a proof in Iwaniec-Kowalski's Analytic Number Theory book

My question is about the end of the proof of theorem 1.1, in page 27.

Namely, it is stated that whenever we have a multiplicative function $f:\mathbb{N} \to \mathbb{C},$ let the sequence $\Lambda_{f}(n)$ be defined via the Dirichlet series $$-\frac{D'_{f}(s)}{D_{f}(s)}=\sum_{1}^{\infty}\Lambda_{f}(n)n^{-s}$$ where $D_{f}=\sum_{1}^{\infty} f(n) n^{-s}$ is the Dirichlet series of $f(n).$ Now let's suppose that $$\sum_{n\leq x}\Lambda_{f}(n)=k \log{x}+O(1)$$ for some constant $k>-\frac{1}{2}$ and that $$\sum_{n \leq x}|f(n)| \ll (\log x)^{|k|}$$

The fact that I am not able to justify is that under these assumptions the following infinite product $$\prod_{p}(1-p^{-s-1})^{k}\left(\sum_{\nu=0}^{\infty}f(p^{\nu})p^{-\nu s}\right)$$ has the following limit as $s \to 0$ from the right $$\prod_{p}(1-p^{-1})^{k}\left(\sum_{\nu=0}^{\infty}f(p^{\nu})\right)$$

Any suggestions on that ?

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