Results 12 issues of Sam Mason

I've just been using your library for parsing some text and it's been very useful. One feature I missed was being able to handle missing values in my `NodeVisitor` nicely...

I've been struggling with iPython 3.2 compatibility and have tracked it down to the changed difference: `execute` isn't an attribute of the `shell_channel`. Seems that since the Jupyter/IPython division `ipykernel`...