code: def _walk(self, root_path='', root_id=''):
          
          ''' a generator method which walks the file structure of the dropbox collection '''
          
          title = '%s._walk' % self.__class__.__name__
          
          if root_id:
              pass
          elif root_path:
              root_id, root_parent = self._get_id(root_path)
          for file_id, name, mimetype in self._list_directory(root_id):
              file_path = os.path.join(root_path, name)
              if mimetype == 'application/vnd.google-apps.folder':
                  for path, id in self._walk(root_path=file_path, root_id=file_id):
                      yield path, id
              else:
                  yield file_path, file_if _walk(self, root_path='', root_id=''):
          
          ''' a generator method which walks the file structure of the dropbox collection '''
          
          title = '%s._walk' % self.__class__.__name__
          
          if root_id:
              pass
          elif root_path:
              root_id, root_parent = self._get_id(root_path)
          for file_id, name, mimetype in self._list_directory(root_id):
              file_path = os.path.join(root_path, name)
              if mimetype == 'application/vnd.google-apps.folder':
                  for path, id in self._walk(root_path=file_path, root_id=file_id):
                      yield path, id
              else:
                  yield file_path, file_id
docs: a generator method which walks the file structure of the dropbox collection