def open_sftp_client(self):
return SFTPClient.from_transport(self)<EOL>
Create an SFTP client channel from an open transport.  On success, an
SFTP session will be opened with the remote host, and a new
`.SFTPClient` object will be returned.

:return:
    a new `.SFTPClient` referring to an sftp session (channel) across
    this transport