Paraproxy (adding Paramiko for SSH2 ProxyCommands) looks like it can do it. There is no documentation online, but when downloading the source and checking the README I found this:
Paraproxy is an addition to the great "paramiko" SSH2 module. Although paramiko has good support for SSH (2), it lacks the function of ProxyCommand.
Proxy commands can be used, for example. to connect to VPN tunnels, but they provide manny with other nice features.
Paraproxy, after import, will be in the SSHClient class provided by paramiko, which, in turn, supports SSH ProxyCommands.
There are no changes to the existing code. necessary.
Give it a shot!
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