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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 get_mor(self, key, name):
 """ Return the Mor object identified by `name` for the given instance key. If the key is not in the cache, raises a KeyError. If there's no Mor with the given name, raises a MorNotFoundError. """

        with self._mor_lock:
            mors = self._mor[key]
            try:
                return mors[name]
            except KeyError:
                raise MorNotFoundError("Mor object '{}' is not in the cache.".format(name))