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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 _initialize_uaa_cache(self):
 """ If we don't yet have a uaa cache we need to initialize it. As there may be more than one UAA instance we index by issuer and then store any clients, users, etc. """

        try:
            os.makedirs(os.path.dirname(self._cache_path))
        except OSError as exc:
            if exc.errno != errno.EEXIST:
                raise

        data = {}
        data[self.uri] = []

        return data