Sphinx extension for automatically numbering ipython blocks.

To use, write your code blocks like so:


.. sourcecode:: ipython

    In [*]: x = 5
    In [*]: y = 9
    In [*]: x*y
    Out[*]: 45
    
    
The code block will appear in the documentation as:

    In [1]: x = 5
    In [2]: y = 9
    In [3]: x*y
    Out[3]: 45