docs: def canonical_name(sgf_name):
      """Keep filename and some date folders"""
      sgf_name = os.path.normpath(sgf_name)
      assert sgf_name.endswith('.sgf'), sgf_name
      # Strip off '.sgf'
      sgf_name = sgf_name[:-4]
  
      # Often eval is inside a folder with the run name.
      # include from folder before /eval/ if part of path.
      with_folder = re.search(r'/([^/]*/eval/.*)', sgf_name)
      if with_folder:
          return with_folder.group(1)
  
      # Return the filename
      return os.path.basename(sgf_name)