\begin{Verbatim}[commandchars=@\[\]]
@PYbc[from] @PYaV[os] @PYbc[import] listdir
@PYbc[from] @PYaV[os.path] @PYbc[import] exists
@PYbc[from] @PYaV[itertools] @PYbc[import] imap

@PYay[print] all(imap(exists, @PYZlb[]@PYaB[']@PYaB[/etc/passwd]@PYaB['],
    @PYaB[']@PYaB[/usr/bin/python]@PYaB[']@PYZrb[]))

@PYay[print] any(item@PYbe[.]endswith(@PYaB[']@PYaB[.py]@PYaB[']) @PYay[for] item @PYav[in] listdir(@PYaB[']@PYaB[.]@PYaB[']))
\end{Verbatim}