Derive DID, as per indy-sdk, from seed.

        :return: DID

async def _seed2did(self) -> str:
        """
        Derive DID, as per indy-sdk, from seed.

        :return: DID
        """

        rv = None
        dids_with_meta = json.loads(await did.list_my_dids_with_meta(self.handle))  # list

        if dids_with_meta:
            for did_with_meta in dids_with_meta:  # dict
                if 'metadata' in did_with_meta:
                    try:
                        meta = json.loads(did_with_meta['metadata'])
                        if isinstance(meta, dict) and meta.get('seed', None) == self._seed:
                            rv = did_with_meta.get('did')
                    except json.decoder.JSONDecodeError:
                        continue  # it's not one of ours, carry on

        if not rv:  # seed not in metadata, generate did again on temp wallet
            temp_wallet = await Wallet(
                self._seed,
                '{}.seed2did'.format(self.name),
                None,
                {'auto-remove': True}).create()

            rv = temp_wallet.did
            await temp_wallet.remove()

        return rv