class_docstr: 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)
      path = os.path.join(base[0], *params)  # noqa: PTH118
      self._optionally_create_directory(path)
      return path
  
imports: from __future__ import annotations
  import os
  from abc import ABC, abstractmethod
  from pathlib import Path
  from typing import TYPE_CHECKING
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: path