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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, command, arg=None, is_eval=False):
 """run command on the server Args: command - command string arg - command argument is_eval - if True execute command as eval return command's result """

        mode = is_eval and 'eval' or 'command'

        if isinstance(arg, tuple):
            name, d = arg
        else:
            name, d = arg, {}

        result = getattr(self.connection.admin, mode)(command, name, **d)
        return result