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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 _load_region(self, acct_id, region_name, path):
 """load config from a single per-region subdirectory of an account"""

        lim_path = os.path.join(path, 'limit_overrides.json')
        thresh_path = os.path.join(path, 'threshold_overrides.json')
        res = {'limit_overrides': {}, 'threshold_overrides': {}}
        if os.path.exists(lim_path):
            with open(lim_path, 'r') as fh:
                res['limit_overrides'] = json.loads(fh.read())
        if os.path.exists(thresh_path):
            with open(thresh_path, 'r') as fh:
                res['threshold_overrides'] = json.loads(fh.read())
        self._config[acct_id]['regions'][region_name] = res