Python Heisenbugs? (was: Re: PyWart: The problem with "print")

[Dan Sommers]

On Mon, 03 Jun 2013 13:37:27 +1000, Tim Delaney wrote:

> With the increase in use of higher-level languages, these days
> Heisenbugs most often appear with multithreaded code that doesn't
> properly protect critical sections, but as you say, with lower-level
> languages uninitialised memory is a common source of them.

Aside from an I/O caching bug directly affected by calling print or
somefile.write (where somefile is stdout), how else could I create a
Heisenbug in pure Python?

To bring this thread back around full circle:  I suppose that if I had a
local function called print, and decided that I needed some debugging
output, I could be in for a surprise; or a local module called logging,
and decided to use the logging module instead of calling print directly.