def export_wif(self) -> str:
        """
        This interface is used to get export ECDSA private key in the form of WIF which
        is a way to encoding an ECDSA private key and make it easier to copy.

        :return: a WIF encode private key.
        """
        data = b''.join([b'\x80', self.__private_key, b'\01'])
        checksum = Digest.hash256(data[0:34])
        wif = base58.b58encode(b''.join([data, checksum[0:4]]))
        return wif.decode('ascii')
This interface is used to get export ECDSA private key in the form of WIF which
        is a way to encoding an ECDSA private key and make it easier to copy.

        :return: a WIF encode private key.