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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_command(self, cmd, argv):
 """ Runs command. :param cmd: command to run (key at the registry) :param argv: arguments passed to the command """

        try:
            Command = self.get_command_class(cmd)
        except CommandError, e:
            self.stderr.write(str(e) + '\n')
            self.show_help()
            sys.exit(-1)
        command = Command(stdout=self.stdout, stderr=self.stderr)
        command.run_from_argv(argv)