code: def _OpenPathSpec(self, path_specification, ascii_codepage='cp1252'):
      
      if not path_specification:
        return None
  
      file_entry = self._file_system.GetFileEntryByPathSpec(path_specification)
      if file_entry is None:
        return None
  
      file_object = file_entry.GetFileObject()
      if file_object is None:
        return None
  
      registry_file = dfwinreg_regf.REGFWinRegistryFile(
          ascii_codepage=ascii_codepage)
  
      try:
        registry_file.Open(file_object)
      except IOError as exception:
        logger.warning(
            'Unable to open Windows Registry file with error: {0!s}'.format(
                exception))
        file_object.close()
        return None
  
      return registry_file
docs: Opens the Windows Registry file specified by the path specification.
  
      Args:
        path_specification (dfvfs.PathSpec): path specification.
        ascii_codepage (Optional[str]): ASCII string codepage.
  
      Returns:
        WinRegistryFile: Windows Registry file or None.