confused by bindings

[Sam Falkner]

Brief recap: I've been trying to write a test for my code, and by best
efforts have been failing in bizarre ways.  I tried four different
ways to write the tests, detailed in the message that this is
following-up.

Alex's follow-up pointed out the flaw in my use of the Borg class.
But, I was much more confused about why the other methods were
failing.

The bottom line: I was doing a bad thing in one of my C extensions.

I started getting other very odd behavior in my app, such as

isinstance(c, data.Cell)

returning false, but c.__class__ is data.Cell, and c is obviously
behaving as a Cell.  When this happened, I went over my C code line by
line.  In one place, I was importing "mod" (name changed to protect
the guilty), and I meant to be importing "pkg.mod".  Because I was
sitting in the same directory as "mod", it didn't fail.  I fixed this,
and these problems have vanished.

                                * * *

Thanks for all the replies, this has been a good learning experience
for me.  Whew!

- Sam