Issue 4382 - Use new syntax to catch exceptions in buildtools

build.py

 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import os
 import sys
 import re
 import subprocess
 import shutil
 import buildtools
@@ skipping 579 matching lines @@
 No command given, assuming "build". For a list of commands run:
 
   %s help
 ''' % scriptName
 
     command = args[0]
     if command in commands:
         if commands[command].isSupported(type):
             try:
                 opts, args = commands[command].parseArgs(type, args[1:])
-            except GetoptError, e:
+            except GetoptError as e:
                 print str(e)
                 usage(scriptName, type, command)
                 sys.exit(2)
             for option, value in opts:
                 if option in ('-h', '--help'):
                     usage(scriptName, type, command)
                     sys.exit()
             commands[command](baseDir, scriptName, opts, args, type)
         else:
             print 'Command %s is not supported for this application type' % command
             usage(scriptName, type)
     else:
         print 'Command %s is unrecognized' % command
         usage(scriptName, type)