     /// - Returns:an instance of `MXSpaceGraphData` if the data has been restored succesfully. `nil` otherwise
     func loadSpaceGraphData() -> MXSpaceGraphData? {
         guard let storeUrl = self.storeUrl else {
-            MXLog.error("[MXSpaceStore] loadSpaceGraphData failed: storeUrl not defined")
+            MXLog.error("[MXSpaceStore] loadSpaceGraphData: failed: storeUrl not defined")
             return nil
         }
         

    /// - Returns: `true` if the data has been stored properly.`false` otherwise
    func store(spaceGraphData: MXSpaceGraphData) -> Bool {
        guard let storeUrl = self.storeUrl else {
            MXLog.error("[MXSpaceStore] storeSpaceGraphData failed: storeUrl not defined")
            return false
        }
        

                }
                try FileManager.default.moveItem(at: fileUrl, to: backupUrl)
            } catch {
                MXLog.error("[MXSpaceFileStore] store: storeSpaceGraphData failed to move graph to backup: \(error)")
            }
        }
        
