def _read_routine_metadata(self):
metadata = {}<EOL>if os.path.isfile(self._metadata_filename):<EOL><INDENT>with open(self._metadata_filename, '<STR_LIT:r>') as file:<EOL><INDENT>metadata = json.load(file)<EOL><DEDENT><DEDENT>return metadata<EOL>
Returns the metadata of stored routines.

:rtype: dict