code: def setPath(self, folderpath, specfiles=None):
          
          if specfiles is None:
              specfiles = [_ for _ in viewkeys(self.info)]
          else:
              specfiles = aux.toList(specfiles)
  
          _containerSetPath(self, folderpath, specfiles)
docs: Changes the folderpath of the specified specfiles. The folderpath is
          used for saving and loading of ``mrc`` files.
  
          :param specfiles: the name of an ms-run file or a list of names. If None
              all specfiles are selected.
          :type specfiles: None, str, [str, str]
          :param folderpath: a filedirectory