102   def _GetOldTag(self, path, subpath=None):  argument
103     return self.old_metadata and self.old_metadata.GetTag(path, subpath)
144     for subpath in self.new_metadata.IterSubpaths(path):
145       if self._GetOldTag(path, subpath) is None:
146         yield subpath
158       for subpath in self.old_metadata.IterSubpaths(path):
159         if self.new_metadata.GetTag(path, subpath) is None:
160           yield subpath
172     for subpath in self.new_metadata.IterSubpaths(path):
173       old_tag = self._GetOldTag(path, subpath)
174       new_tag = self.new_metadata.GetTag(path, subpath)
176         yield subpath
329   def _GetEntry(self, path, subpath=None):  argument
337     return self._file_map.get((path, subpath))
339   def GetTag(self, path, subpath=None):  argument
341     ret = self._GetEntry(path, subpath)