import reimport datetimeimport osimport sysstr1 = ‘350825198808080808‘pat = re.search(r‘[1-9][0-9]{5}([0-9]{4})([0-9]{2})([0-9]{2})[0-9]{3}[0-9X]‘, str1)if len(str1) != 18 or not pat:    print "inValid"    sys.exit(1)try:    datetime.date(int(pat.group(1)),int(pat.group(2)),int(pat.group(3)))except ValueError,e:    print e    sys.exit(1)except:    sys.exit(1)print "Valid"