def _get_flattened_sizes(self):
        return [[(n, acc.meta['size']) for n, acc in iteritems(self._dat)
                        if not acc.pbo]]
If the client has no certificate initially it should enroll.
dataset/ETHPy150Open OpenMDAO/OpenMDAO/openmdao/core/vec_wrapper.py/SrcVecWrapper._get_flattened_sizes--crossover with--dataset/ETHPy150Open google/grr/grr/lib/communicator_test.py/HTTPClientTests.testInitialEnrollment