If f(y)=log4(csc(y))\displaystyle {f{{\left({y}\right)}}}={{\log}_{{4}}{\left({\csc{{\left({y}\right)}}}\right)}}, find f(y)\displaystyle {f}'{\left({y}\right)}. Use exact values.

f(y)=\displaystyle {f}'{\left({y}\right)}=