append_const is not supported on python 2.4....

trychange.py

 #!/usr/bin/python
 # Copyright (c) 2009 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 """Client-side script to send a try job to the try server. It communicates to
 the try server by either writting to a svn repository or by directly connecting
 to the server by HTTP.
 """
 
 import datetime
@@ skipping 457 matching lines @@
                    help="Root to use for the patch; base subdirectory for "
                         "patch created in a subdirectory")
   group.add_option("-p", "--patchlevel", type='int', metavar="LEVEL",
                    help="Used as -pN parameter to patch")
   group.add_option("-s", "--sub_rep", action="append", default=[],
                    help="Subcheckout to use in addition. This is mainly "
                         "useful for gclient-style checkouts. Use @rev or "
                         "@branch or @branch1..branch2 to specify the "
                         "revision/branch to diff against.")
   # Mostly chromium-specific
-  group.add_option("--webkit", action="append_const",
-                   const="third_party/WebKit",
-                   dest="sub_rep",
-                   help="Shorthand for -s third_party/WebKit")
+  try:
+    group.add_option("--webkit", action="append_const",
+                     const="third_party/WebKit",
+                     dest="sub_rep",
+                     help="Shorthand for -s third_party/WebKit")
+  except optparse.OptionError:
+    # append_const is not supported on 2.4. Too bad.
+    pass
   group.add_option("--no_gclient", action="store_true",
                    help="Disable automatic search for gclient checkout.")
   parser.add_option_group(group)
 
   group = optparse.OptionGroup(parser, "Access the try server by HTTP")
   group.add_option("--use_http",
                    action="store_const",
                    const=_SendChangeHTTP,
                    dest="send_patch",
                    help="Use HTTP to talk to the try server [default]")
@@ skipping 126 matching lines @@
   except (InvalidScript, NoTryServerAccess), e:
     if swallow_exception:
       return 1
     print e
     return 1
   return 0
 
 
 if __name__ == "__main__":
   sys.exit(TryChange(None, [], False))