\begin{Verbatim}[commandchars=\\\{\}]
\PYG{g+go}{\PYGZsh{} Get some atoms}
\PYG{g+gp}{\PYGZgt{}\PYGZgt{}\PYGZgt{} }\PYG{n}{ca1} \PYG{o}{=} \PYG{n}{residue1}\PYG{p}{[}\PYG{l+s+s2}{\PYGZdq{}CA\PYGZdq{}}\PYG{p}{]}
\PYG{g+gp}{\PYGZgt{}\PYGZgt{}\PYGZgt{} }\PYG{n}{ca2} \PYG{o}{=} \PYG{n}{residue2}\PYG{p}{[}\PYG{l+s+s2}{\PYGZdq{}CA\PYGZdq{}}\PYG{p}{]}
\PYG{g+go}{\PYGZsh{} Simply subtract the atoms to get their distance}
\PYG{g+gp}{\PYGZgt{}\PYGZgt{}\PYGZgt{} }\PYG{n}{distance} \PYG{o}{=} \PYG{n}{ca1}\PYG{o}{\PYGZhy{}}\PYG{n}{ca2}
\end{Verbatim}
