virtual [OPERATION_ID](API\Plugins\MutableRuntime\MuR\ModelReader\OPERATION_ID) BeginReadBlock ( const [mu::Model](API\Plugins\MutableRuntime\MuR\Model) *, uint64 key0, void * pBuffer, uint64 size, [TFunction](API\Runtime\Core\GenericPlatform\TFunction)< void(boolbSuccess)> * CompletionCallback )