code: def folder(self, folder):
          
          result = []
          for root, _, files in os.walk(folder):
              for file in files:
                  path = os.path.join(root, file)
                  if self._chooses_path(path):
                      result.append(self.path(path))
          return result
docs: Load all files from a folder recursively.
  
          Depending on :meth:`chooses_path` some paths may not be loaded.
          Every loaded path is processed and returned part of the returned list.
  
          :param str folder: the folder to load the files from
          :rtype: list
          :return: a list of the results of the processing steps of the loaded
            files