Tunnel

TCP tunnel to a port inside a sandbox.

Opens a local TCP listener and forwards each accepted connection through a yamux-multiplexed WebSocket to the daemon, which dials the target port inside the sandbox.

Typically used as a context manager::

with sandbox.tunnel(remote_port=5432) as t:
    conn = psycopg2.connect(host="127.0.0.1", port=t.local_port)

Or with explicit lifecycle::

t = sandbox.tunnel(remote_port=5432)
# ... use tunnel ...
t.close()