class_docstr: Abstract base class for platform directories.
class_docstr_tok: ["Abstract","base","class","for","platform","directories","."]
code: def _append_app_name_and_version(self, *base: str) -> str:
      params = list(base[1:])
      if self.appname:
          params.append(self.appname)
          if self.version:
              params.append(self.version)
      return os.path.join(base[0], *params)
  
imports: from __future__ import annotations
  import os
  import sys
  from abc import ABC, abstractmethod
  from pathlib import Path
label_desc: Use image node_id 2 for calling the PlatformDirsABC obj's underlying member method code with example usage: obj._append_app_name_and_version() and returns: os