I have a problem figuring out a somewhat simple twisted python code. From what I have red in the docs, the code here should work without Unhandled Error.

I get this:

HELLO!
HANDLED!
HANDLED 2!
Unhandled error in Deferred:
Unhandled Error
Traceback (most recent call last):
  File "package_tester.py", line 31, in <module>
    a().callback(2)
  File "/usr/local/lib/python2.7/dist-packages/twisted/internet/defer.py", line 368, in callback
    self._startRunCallbacks(result)
  File "/usr/local/lib/python2.7/dist-packages/twisted/internet/defer.py", line 464, in _startRunCallbacks
    self._runCallbacks()
--- <exception caught here> ---
  File "/usr/local/lib/python2.7/dist-packages/twisted/internet/defer.py", line 551, in _runCallbacks
    current.result = callback(current.result, *args, **kw)
  File "package_tester.py", line 5, in c
    raise Exception()
exceptions.Exception:

Isn't the failure from the chained deferred passed to end() errback ?