def dummy_signatures(self):
if not self.signing_algorithm:<EOL><INDENT>return []<EOL><DEDENT>algo_id = {'<STR_LIT>': <NUM_LIT:1>, '<STR_LIT>': <NUM_LIT:2>}[self.signing_algorithm]<EOL>signature = make_dummy_signature(algo_id)<EOL>return [(algo_id, signature)]<EOL>
Create a dummy signature.

        This is used when initially writing the MAR header and we don't know
        what the final signature data will be.

        Returns:
            Fake signature data suitable for writing to the header with
            .write_signatures()