\begin{Verbatim}[commandchars=\\\{\}]
\PYG{g+gp}{\PYGZgt{}\PYGZgt{}\PYGZgt{} }\PYG{n}{counts}\PYG{p}{[}\PYG{l+s+s1}{\PYGZsq{}A\PYGZsq{}}\PYG{p}{,} \PYG{l+s+s1}{\PYGZsq{}C\PYGZsq{}}\PYG{p}{]} \PYG{o}{=} \PYG{l+m+mf}{12.0}
\PYG{g+gp}{\PYGZgt{}\PYGZgt{}\PYGZgt{} }\PYG{n}{counts}\PYG{p}{[}\PYG{l+m+mi}{2}\PYG{p}{,} \PYG{l+m+mi}{1}\PYG{p}{]} \PYG{o}{=} \PYG{l+m+mf}{5.0}
\PYG{g+gp}{\PYGZgt{}\PYGZgt{}\PYGZgt{} }\PYG{n}{counts}\PYG{p}{[}\PYG{l+m+mi}{3}\PYG{p}{,} \PYG{l+s+s1}{\PYGZsq{}T\PYGZsq{}}\PYG{p}{]} \PYG{o}{=} \PYG{o}{\PYGZhy{}}\PYG{l+m+mi}{2}
\PYG{g+gp}{\PYGZgt{}\PYGZgt{}\PYGZgt{} }\PYG{n+nb}{print}\PYG{p}{(}\PYG{n}{counts}\PYG{p}{)}
\PYG{g+go}{    A    C   G    T}
\PYG{g+go}{A 0.0 12.0 0.0  0.0}
\PYG{g+go}{C 0.0  0.0 0.0  0.0}
\PYG{g+go}{G 0.0  5.0 0.0  0.0}
\PYG{g+go}{T 0.0  0.0 0.0 \PYGZhy{}2.0}
\PYG{g+go}{\PYGZlt{}BLANKLINE\PYGZgt{}}
\PYG{g+gp}{\PYGZgt{}\PYGZgt{}\PYGZgt{} }\PYG{n}{counts}\PYG{p}{[}\PYG{l+s+s1}{\PYGZsq{}X\PYGZsq{}}\PYG{p}{,} \PYG{l+m+mi}{1}\PYG{p}{]}
\PYG{g+gt}{Traceback (most recent call last):}
    \PYG{o}{...}
\PYG{g+gr}{IndexError}: \PYG{n}{\PYGZsq{}X\PYGZsq{}}
\PYG{g+gp}{\PYGZgt{}\PYGZgt{}\PYGZgt{} }\PYG{n}{counts}\PYG{p}{[}\PYG{l+s+s1}{\PYGZsq{}A\PYGZsq{}}\PYG{p}{,} \PYG{l+m+mi}{5}\PYG{p}{]}
\PYG{g+gt}{Traceback (most recent call last):}
    \PYG{o}{...}
\PYG{g+gr}{IndexError}: \PYG{n}{index 5 is out of bounds for axis 1 with size 4}
\end{Verbatim}
