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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_client(self):
 """ OSS2 Auth client Returns: oss2.Auth or oss2.StsAuth: client """

        return (_oss.StsAuth if 'security_token' in self._storage_parameters
                else _oss.Auth if self._storage_parameters
                else _oss.AnonymousAuth)(**self._storage_parameters)