Introduced docs changes to indicate Python 3 compatability

[cmonr]

No description provided.

[MarceloSalazar]

@cmonr thanks for the update on docs.

As discussed with @BlackstoneEngineering, it's important that we clarify the backwards compatibility problem, as Python 3 tools won't work with OS < v5.8.

[cmonr]

@MarceloSalazar Did you have something more specific in mind aside from e388e15 ?

[MarceloSalazar]

@cmonr the last update is great! - I was reviewing an old version :)

What would happen if someone attempts to use Python 3 with a previous Mbed OS?
Would it should a clear error to the user?

[cmonr]

@MarceloSalazar mbed-cli would most likely error with something cryptic, similar to what @ashok-rao first got when he tried to test on Windows this week.

However, I don't like the idea of introducing something that would do a live version check in mbed-cli, since mbed-cli is often used with detached versions of mbed-os, making version confirmation much more nuanced and time consuming.

[MarceloSalazar]

making version confirmation much more nuanced and time consuming.

This is a serious UX problem and not acceptable.

We can't release something that is known to cause serious python traceback errors for many Mbed users.

If we don't have time to fix the tools, then let's delay the update on the docs until it's done, and set expectations accordingly.

[cmonr]

@MarceloSalazar Should be doing a similar check with the pip version compatibility?

https://github.com/ARMmbed/Handbook/pull/549/files

[SenRamakri]

Looks good to me. I do understand the backward compatibility issue @MarceloSalazar mentioned. But from the docs perspective, this looks good to me.

[MarceloSalazar]

If we decide to go ahead, I'd like to have a known issue open with the release and start working to deliver a fix in a patch release

@adbridge FYI

[theotherjimmy]

A fix for what exactly @MarceloSalazar?

[MarceloSalazar]

@theotherjimmy see error and proposed solution in ARMmbed/mbed-cli#686

[AnotherButler]

So do we have a code dependency for this document?

[cmonr]

@AnotherButler I think so? I'm not sure what a code dependency implies in Handbook PRs.

There are a couple of moving pieces still, but here's the remaining list:

• Added warning message about Mbed OS Py3 compatability mbed-cli#689: Adding a message to warn users of Py3 backwards-incompatabiltiy with Mbed OS <=5.8
  • Discussion still ongoing about if anything else is needed: Traceback error when using v1.7.2 + Python 3 mbed-cli#686
  • Needs to be merged, and Mbed CLI released to 1.7.3.
• Additional fixes for running Python 3 in Windows mbed-os#7092: Fixes for Windows execution, specific for Py3.
  • PR moving through CI, should be merged soon.
• mbed cli export error on Python3 mbed-os#7101: Issue in the process of being resolved. No PR as of yet.

[AnotherButler]

Should we wait for any of the mbed-os PRs to merge before merging this doc PR?

[cmonr]

@AnotherButler I think we're fine to move forward with this PR outside of the above requirements. In any case, the above notes are all making quick progress on being resolved.