issues with doctest and threads

[Michele Simionato]

Thank you for your replies Jeff & Tim. The snippet I submitted is
unfortunate,
since I was writing an example (for a Python course I am going to give
in
September) to show that you cannot reliably assume that you will get
exactly 9 dots, because of the limitations of 'sleep'. Mindlessly, I
have
cut & pasted that snippet, but my real question was not "how many dots
I get", it was:
"why the error message talks about 'thread' not being in the globals?"
It's true that I can avoid it with a thread.join() (which I had
forgot),
but still I really cannot understand the reason for such message. Why
it
is so misleading? Can something be done about it?
TIA,
                      Michele Simionato