\begin{flushleft}
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\vspace*{-4mm}

\begin{alltt}
STk> (define g (graph '(1 2 3) '((1 2) (1 3) (3 1)))){\em{
\#[undefined]} }
\end{alltt}
\begin{alltt}
STk> (map (lambda (x) 
            (find-string-attribute 'vcolor x)) 
          (set-vertex->list (vertices g))){\em{
("blue" "blue" "blue")} }
\end{alltt}

\vspace*{-5mm}

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