306       \begin{lstlisting}

   306       \begin{lstlisting}

   307 >>> from math import sqrt

   307 >>> from math import sqrt

   308 >>> from math import *

   308 >>> from math import *

   309       \end{lstlisting}    

   309       \end{lstlisting}    

   310     \item What is the difference?

   310     \item What is the difference?

   312     \end{itemize}

   312     \end{itemize}

   313   \emphbar{Package hierarchies}

   313   \emphbar{Package hierarchies}

   314       \begin{lstlisting}

   314       \begin{lstlisting}

   315 >>> from os.path import exists

   315 >>> from os.path import exists

   316       \end{lstlisting}

   316       \end{lstlisting}