code: def createStore(self, debug, journalMode=None):
          
          if self.storepath is None:
              self.store._memorySubstores.append(self) # don't fall out of cache
              if self.store.filesdir is None:
                  filesdir = None
              else:
                  filesdir = (self.store.filesdir.child("_substore_files")
                                                 .child(str(self.storeID))
                                                 .path)
              return Store(parent=self.store,
                           filesdir=filesdir,
                           idInParent=self.storeID,
                           debug=debug,
                           journalMode=journalMode)
          else:
              return Store(self.storepath.path,
                           parent=self.store,
                           idInParent=self.storeID,
                           debug=debug,
                           journalMode=journalMode)
docs: Create the actual Store this Substore represents.