Is there an expression that contains factor $\frac{1}{e^x - 1}$?

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We know that some expressions of $\zeta (s)$ contains the factor: ${\frac {1}{e^{x}-1}}$.

For example:

${\displaystyle 2\sin(\pi s)\Gamma (s)\zeta (s)=i\oint _{H}{\frac {(-x)^{s-1}} {e^{x}-1}}\,\mathrm {d} x}$

For Riemann $\xi (s)$:

$\xi (s)={\tfrac {1}{2}}s(s-1)\pi ^{{-s/2}}\Gamma \left({\tfrac {1}{2}}s\right)\zeta (s)$

Is there a simple expression for it which contains the factor ${\frac {1}{e^{x}-1}}$ ?

In other words, is there a simple relation between $\xi (s)$ and the factor ${\frac {1}{e^{x}-1}}$ ?