bool RetrieveChunk ( const TPair< [FIoContainerId](API\Runtime\Core\IO\FIoContainerId), [FIoChunkHash](API\Runtime\Core\IO\FIoChunkHash) > & InChunkKey, [TUniqueFunction](API\Runtime\Core\Templates\TUniqueFunction)< void([TIoStatusOr](API\Runtime\Core\IO\TIoStatusOr)< [FIoStoreCompressedReadResult](API\Runtime\Core\IO\FIoStoreCompressedReadResult) >)> InCompletionCallback )