<p>Which are the most advanced frameworks and tools there are available for python for practicing Behavior Driven Development? Especially finding similar tools as rspec and mocha for ruby would be great.</p>

I am probably completely missing the point, but what I retained of the
original BDD paper
was that BDD was just
TDD
repackaged to emphasize some best practices.
If my interpretation is correct, you can get a BDD framework just by renaming methods around in any
xUnit
implementation. So just go ahead and use the standard library's
unittest
.
EDIT: A quick google turned up a
Behaviour
module in the
Cheese Shop
. Further
searching
for BDD there did not find anything else.