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$$
H(z)={\frac  {(1-q_{1}z^{{-1}})(1-q_{2}z^{{-1}})...(1-q_{M}z^{{-1}})}{(1-p_{1}z^{{-1}})(1-p_{2}z^{{-1}})...(1-p_{N}z^{{-1}})}}\ 
$$
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