#NEWLINE# def test_detach_detached_volume( self ) : #NEWLINE# #INDENT# '\n        ``detach_volume`` raises ``UnattachedVolume`` if the supplied\n        ``blockdevice_id`` is not attached to a host.\n        ' #NEWLINE# volume = self . api . create_volume ( dataset_id = uuid4 ( ) , size = self . minimum_allocatable_size ) #NEWLINE# exception = self . assertRaises ( UnattachedVolume , volume . api . detach_volume , volume . blockdevice_id ) #NEWLINE# self . assertEqual ( exception . args , ( volume . blockdevice_id , ) )