Import error in ipython for AplPy

Question

I am trying to start up AplPy on OSX by importing it on ipython. I installed AplPy using pip, and then in the terminal I entered:

 ipython --pylab 
 import aplpy 

However I only get the following output:

/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/IPython/kernel/_
_init__.py:13: ShimWarning: The `IPython.kernel` package has been deprecated.
You should import from ipykernel or jupyter_client instead.
"You should import from ipykernel or jupyter_client instead.", ShimWarning)
---------------------------------------------------------------------------
ImportError                               Traceback (most recent call last)
<ipython-input-3-429eb0b27113> in <module>()
----> 1 import aplpy

/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-        packages/aplpy/__init__.py in <module>()
 12 if not _ASTROPY_SETUP_:
 13 
---> 14     from .core import FITSFigure
 15     from .rgb import make_rgb_image, make_rgb_cube
 16 

/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-    packages/aplpy/core.py in <module>()
 12 
 13 import matplotlib.pyplot as mpl
---> 14 import mpl_toolkits.axes_grid.parasite_axes as mpltk
 15 from astropy.extern import six
 16 

/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/mpl_toolkits/axes_grid/__init__.py in <module>()
  2                         unicode_literals)
  3 
----> 4 from matplotlib.externals import six
  5 
  6 from . import axes_size as Size

ImportError: No module named externals

I couldnt find anywhere online a module named externals that could possibly be missing, would anyone else have any idea what's going on?