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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 run(opts, args):
        '''The run method for the 'run' command. Executes a plugin from the
        command line.
        '''
        setup_options(opts)

        mode = Modes.ONCE
        if len(args) > 0 and hasattr(Modes, args[0].upper()):
            _mode = args.pop(0).upper()
            mode = getattr(Modes, _mode)

        url = None
        if len(args) > 0:
            # A url was specified
            url = args.pop(0)

        plugin_mgr = PluginManager.load_plugin_from_addonxml(mode, url)
        plugin_mgr.run()