C API []-style access to instance objects

[williams.jasonscott at gmail.com]

Hi,

I am having trouble figuring out how to set up an object to be
scriptable through the C API.  An example of what I am attempting to
do:

>>> obj = foo.Foo()
>>> obj["key"]
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
TypeError: unsubscriptable object
>>>

I've tried defining __getitem__ as a method, but that hasn't worked.
Is there a tp_field that I am failing to understand, something like
tp_iter and tp_iternext?  

thanks~