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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 default(self, argv):
 """Hook called to handle a command for which there is no handler. "argv" is the command and arguments to run. The default implementation writes an error message to stderr and returns an error exit status. Returns a numeric command exit status. """

        errmsg = self._str(self.unknowncmd % (argv[0], ))
        if self.cmdlooping:
            self.stderr.write(errmsg + "\n")
        else:
            self.stderr.write("%s: %s\nTry '%s help' for info.\n" %
                              (self._name_str, errmsg, self._name_str))
        self.stderr.flush()
        return 1