Mittag Leffler expansion for (csch(z))^2



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(C2) csch(z)^2;
(D2) CSCH(z)^2
(C3) subst(z*%i,z,d2);
(D3) -CSC(z)^2
(C4) trigrat(d3);
(D4) 2/(COS(2*z)-1)
(C5) subst(z/%i,z,d4);
(D5) 2/(COSH(2*z)-1)