#!/usr/bin/env python
     # encoding: utf-8
     #
     # Copyright (c) 2010 Doug Hellmann.  All rights reserved.
     #
     """Square roots
     """
     #end_pymotw_header
     
     import math
     
     print math.sqrt(9.0)
     print math.sqrt(3)
     try:
         print math.sqrt(-1)
     except ValueError, err:
         print 'Cannot compute sqrt(-1):', err