This happens when the sys.paths of Python and IPython are different. To check the paths, enter the code below in each shell.

In the Python shell:

>>> import sys, pprint
>>> pprint.pprint(sys.path)
['',
 '/Library/Python/2.7/site-packages',
 '/usr/local/Cellar/python/2.7.9/Frameworks/Python.framework/Versions/2.7/lib/python27.zip',
 '/usr/local/Cellar/python/2.7.9/Frameworks/Python.framework/Versions/2.7/lib/python2.7',
 '/usr/local/Cellar/python/2.7.9/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-darwin',
 '/usr/local/Cellar/python/2.7.9/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac',
 '/usr/local/Cellar/python/2.7.9/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac/lib-scriptpackages',
 '/usr/local/Cellar/python/2.7.9/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk',
 '/usr/local/Cellar/python/2.7.9/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-old',
 '/usr/local/Cellar/python/2.7.9/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload',
 '/usr/local/lib/python2.7/site-packages']
>>>

In the IPython shell:

In [1]: import sys
In [2]: sys.path
Out[2]:
['',
 '/usr/local/bin',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python27.zip',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-darwin',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac/lib-scriptpackages',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-old',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/PyObjC',
 '/Library/Python/2.7/site-packages',
 '/Library/Python/2.7/site-packages/IPython/extensions',
 '/Users/username/.ipython']
In [3]:

In most cases, there will be a missing path from IPython’s sys.path. In this case, that path is /usr/local/lib/python2.7/site-packages. Now let’s try adding this path to IPython’s sys.path.

Temporary solution

If a path exists in Python but is missing in IPython, you can temporarily add the corresponding path to IPython using sys.path.append. For example, if /usr/local/lib/python2.7/site-packages was missing from your IPython path, you can append it as below in the IPython shell:

In [1]: import sys
In [2]: sys.path.append('/usr/local/lib/python2.7/site-packages')

Permanant solution

  1. Enter the following in the terminal. ipython profile create will create a new IPython profile, and ipython locate will tell you where your IPython profile is located. Of course, your IPython profile path will probably be different with the example below.

     $ ipython profile create
 $ ipython locate
 /Users/username/.ipython

  2. Move to the path of your IPython profile printed above, and open the file profile_default/ipython_config.py.

     $ cd /Users/username/.ipython
 $ vi profile_default/ipython_config.py

    Add the following to profile_default/ipython_config.py.

     c.InteractiveShellApp.exec_lines = [
     'import sys; sys.path.append("/usr/local/lib/python2.7/site-packages")'
 ]