def rvs(self, size=1):
        raise NotImplementedError
``create_volume`` raises ``ValueError`` unless the supplied
dataset/ETHPy150Open statsmodels/statsmodels/statsmodels/sandbox/distributions/mv_normal.py/MVElliptical.rvs--crossover with--dataset/ETHPy150Open ClusterHQ/flocker/flocker/node/agents/test/test_blockdevice.py/LoopbackBlockDeviceAPIImplementationTests.test_create_with_non_allocation_unit