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\subsection*{Answer}

Begin by recursively defining an operator $SetToSeq$ such that
$SetToSeq(S)$ is some sequence containing every element of the set $S$
exactly once.  Then define $GeneralSortSet(S, LEQ(\_,\,\_))$ to equal
$SortSeq(SetToSeq(S), LEQ)$.  Don't forget to add the $TLC$ module to
the list of modules imported by the \textsc{extends} statement.

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