- Search: https://www.phind.com/search?cache=s4e576jlnp1mpw73n9iy4sqc
- Chat: https://www.phind.com/agent?cache=clsyev95o0006le08b5pjrs14
The search was heavily diluted by authentication methods that don't make any sense for machine-to-machine authentication, like multi-factor or biometric authentication, as well as the advice to combine several methods. It also falls into the, admittedly common, trap of assuming that certificate based authentication is more difficult to implement than symmetric key (i.e. pre-shared key) authentication.
The chat answer is not perfect, but the signal-to-noise ratio is much better. The multi-factor authentication advice is again present, but it's the only major error, and it also adds relevant side-topics that point in the right direction (secure credential storage, secure boot, logging of auth attempts). The Python example is cute, but completely useless, though (Python for embedded devices is rare and in any case you wouldn't want a raw TLS socket, but use it in a MQTTS / HTTPS / CoAP+DTLS stack, and last but not least, it provides a server instead of client, even though IoT devices mostly communicate outbound).