Get the information items from the specified os-release file.

        Returns:
            A dictionary containing all information items.

def _os_release_info(self):
        """
        Get the information items from the specified os-release file.

        Returns:
            A dictionary containing all information items.
        """
        if os.path.isfile(self.os_release_file):
            with open(self.os_release_file) as release_file:
                return self._parse_os_release_content(release_file)
        return {}