emacs hangs when the output to ob-ipython-stdout is too long?

Hi,

If x is too large in the code below, my emacs session hangs:

``` python
#+BEGIN_SRC ipython :export none
x=30000
for i in range(0,x):
print('This is a generic sentence')
#+END_SRC
```

I am using IPython 4.0 and python 2.7.10. Has anyone else encountered this issue?