Question about official API

[Frank Millman]

Hi all

What is the rule for knowing if something is part of the official API?

I have a queue.Queue(), I want to call q.join(), but I do not want it to 
block.

Looking at dir(q), I find an attribute 'unfinished_tasks'. It is an integer, 
and it looks like the counter referred to in the documentation for 
'task_done()'. I tried it out, and it does exactly what I want.

However, it is not mentioned in the documentation.

How do I know if it is safe to rely on this?

Thanks

Frank Millman