"Exception ... in <generator object ...> ignored" Messages

[Ami Tavory]

Hi,

Running the unit tests for some generator code, prints, as a side effect,
numerous messages of the form:

....
Exception NameError: "global name 'l' is not defined" in <generator object
_dagpype_internal_fn_act at 0x9d4c500> ignored
Exception AttributeError: "'NoneType' object has no attribute 'close'" in
<generator object split at 0x7601640> ignored
Exception AttributeError: "'NoneType' object has no attribute 'close'" in
<generator object split at 0x7601690> ignored
....

The tests otherwise run fine.

Is there any way to catch the point where such a message originates, and
print a traceback? I find it difficult to debug otherwise. I've tried
running Python with -W error, catching warnings with context managers, and
so forth, but without any success.

Thanks!