Laurent series $f(z)=\frac{z}{\cos(\frac{\pi}{2z-2})}$ in $z=2$

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How to develop in Laurent series the following function in $z=2$

$$f(z)= \frac{z}{\cos(\frac{\pi}{2z-2})}$$ My problem is that I can not develop

$$f(z) = \frac{1}{\cos(\frac{\pi}{2z-2})}$$

Thank you everybody