Finding a Laurent polynomial that behaves at a pole like a given function

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I need to find a polynomial $P$ such that $P(1/x)$ behaves like given function $f(x)$ at zero (their difference vanishes), even if $f(x)$ has a pole at $0$ or unknown order.

P.S. I need to find a general form for principal part of Laurent series of $\Gamma (n) (-\ln (q+1))^{-n}$