Retrieves the meta information for the giving key in the wallet.

    :param wallet_handle: Wallet handle (created by open_wallet).
    :param verkey: The key (verkey, key id) to retrieve metadata.
    :return: metadata: The meta information stored with the key; Can be null if no metadata was saved for this key.

async def get_key_metadata(wallet_handle: int,
                           verkey: str) -> str:
    """
    Retrieves the meta information for the giving key in the wallet.

    :param wallet_handle: Wallet handle (created by open_wallet).
    :param verkey: The key (verkey, key id) to retrieve metadata.
    :return: metadata: The meta information stored with the key; Can be null if no metadata was saved for this key.
    """

    logger = logging.getLogger(__name__)
    logger.debug("get_key_metadata: >>> wallet_handle: %r, verkey: %r",
                 wallet_handle,
                 verkey)

    if not hasattr(get_key_metadata, "cb"):
        logger.debug("get_key_metadata: Creating callback")
        get_key_metadata.cb = create_cb(CFUNCTYPE(None, c_int32, c_int32, c_char_p))

    c_wallet_handle = c_int32(wallet_handle)
    c_verkey = c_char_p(verkey.encode('utf-8'))

    metadata = await do_call('indy_get_key_metadata',
                             c_wallet_handle,
                             c_verkey,
                             get_key_metadata.cb)

    res = metadata.decode()

    logger.debug("get_key_metadata: <<< res: %r", res)
    return res