importing: what does "from" do?

[Charles T. Smith]

On Thu, 21 Jan 2016 15:44:43 +0000, John Gordon wrote:

> In that case, the problem is most likely a circular import issue, as you
> mentioned.  The only way to fix it is to reorganize your modules.
> 
> How did this error come up?  Did the code work previously?  If so, what
> changed?


What I need is tools to find the problems.  In particular, why doesn't
python give me more of a clue where the problem is?  It would be cool
if it would tell me exactly what module to look at, which symbol(s)
were colliding.

The suggestion of using
pp dict (sys.modules)
might be useful, I need to study it in more detail.