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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 set_threshold_override(self, limit_name, warn_percent=None, warn_count=None, crit_percent=None, crit_count=None):
 """ Override the default warning and critical thresholds used to evaluate the specified limit's usage. Theresholds can be specified as a percentage of the limit, or as a usage count, or both. :param warn_percent: new warning threshold, percentage used :type warn_percent: int :param warn_count: new warning threshold, actual count/number :type warn_count: int :param crit_percent: new critical threshold, percentage used :type crit_percent: int :param crit_count: new critical threshold, actual count/number :type crit_count: int """

        try:
            self.limits[limit_name].set_threshold_override(
                warn_percent=warn_percent,
                warn_count=warn_count,
                crit_percent=crit_percent,
                crit_count=crit_count
            )
        except KeyError:
            raise ValueError("{s} service has no '{l}' limit".format(
                s=self.service_name,
                l=limit_name))