To remain compatible with Paramiko, support for DSA key algo should be removed, i.e., on this line:

Paramiko changelog (https://www.paramiko.org/changelog.html):

[Support] #973: Removed support for the DSA (aka DSS) key algorithm, as it has been badly outdated and insecure for a decade or more at this point, and was recently completely removed from OpenSSH as well.
If you were still using DSA out of sheer inertia: we strongly recommend upgrading to Ed25519 (or maybe ECDSA).

Corresponding error message:

  File "/usr/local/lib/python3.11/site-packages/sshtunnel.py", line 1093, in get_keys

    'dsa': paramiko.DSSKey,

           ^^^^^^^^^^^^^^^

AttributeError: module 'paramiko' has no attribute 'DSSKey'