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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 _reset_param(self, param):
 """ Resets a single parameter :param param: A configuration parameter :type param: str """

        if param not in self._instance.CONFIG_PARAMS:
            raise ValueError("Cannot reset unknown parameter '{}'".format(param))
        setattr(self, param, self._instance.CONFIG_PARAMS[param])