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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def main(argv, reactor=None):
 """Run the client GUI. Typical use: @param argv: The arguments to run it with, e.g. sys.argv. @param reactor: The reactor to use. Must be compatible with gtk as this module uses gtk API"s. @return exitcode: The exit code it returned, as per sys.exit. """

    if reactor is None:
        from twisted.internet import gtk2reactor
        gtk2reactor.install()
        from twisted.internet import reactor
    try:
        AWSStatusIndicator(reactor)
        gobject.set_application_name("aws-status")
        reactor.run()
    except ValueError:
        # In this case, the user cancelled, and the exception bubbled to here.
        pass