"""Convert to and from Roman numeralsThis program is part of "Dive Into Python", a free Python book forexperienced programmers.  Visit http://diveintopython.org/ for thelatest version."""__author__ = "Mark Pilgrim (mark@diveintopython.org)"__version__ = "$Revision: 1.2 $"__date__ = "$Date: 2004/05/05 21:57:20 $"__copyright__ = "Copyright (c) 2001 Mark Pilgrim"__license__ = "Python"#Define exceptionsclass RomanError(Exception): passclass OutOfRangeError(RomanError): passclass NotIntegerError(RomanError): passclass InvalidRomanNumeralError(RomanError): passdef toRoman(n):    """convert integer to Roman numeral"""    passdef fromRoman(s):    """convert Roman numeral to integer"""    pass