\begin{frame}[fragile]
\frametitle{Some Python Code}
\begin{verbatim}
for i in range(1, 5):
  print i
else:
  print "The for loop is over"
\end{verbatim}
\end{frame}

If you want to highlight within a verbatim, then you’d probably want to use the fancyvrb package (and the color package) and do something like:

\begin{frame}[fragile]
\frametitle{Some Python Code}
\newcommand\codeHighlight[1]{\textcolor[rgb]{1,0,0}{\textbf{#1}}}
\begin{Verbatim}[commandchars=\\\{\}]
\codeHighlight{for} i in range(1, 5):
  print i
else:
  print "The for loop is over"
\end{Verbatim}
\end{frame}

The Pygments package in Python will also output syntax highlighted latex code with something like: pygmentize -f latex -O full test.py >py.tex.

Hmm this ended up getting pretty long. I may have to throw this into a post this evening.