iPython notebook on Mac OSX Yosemite: no module named jinja2, even if it's installed
Question: I am trying to run iPython notebook on OSX Yosemite. I have installed
everything via

    
    
    pip install ipython[all]
    

and I see

    
    
    mattia:~ mattiaspeziali$ pip freeze
    backports.ssl-match-hostname==3.4.0.2
    certifi==14.5.14
    docutils==0.12
    gnureadline==6.3.3
    ipython==2.3.1
    Jinja2==2.7.3
    MarkupSafe==0.23
    nose==1.3.4
    numpy==1.8.2
    numpydoc==0.5
    pandas==0.14.1
    Pygments==2.0.1
    pyzmq==14.4.1
    Sphinx==1.2.3
    tornado==4.0.2
    vboxapi==1.0
    

However, jinja2 seems not installed properly:

    
    
        mattia:~ mattiaspeziali$ ipython notebook
    Traceback (most recent call last):
      File "/usr/local/bin/ipython", line 11, in <module>
        sys.exit(start_ipython())
      File "/Library/Python/2.7/site-packages/IPython/__init__.py", line 120, in start_ipython
        return launch_new_instance(argv=argv, **kwargs)
      File "/Library/Python/2.7/site-packages/IPython/config/application.py", line 563, in launch_instance
        app.initialize(argv)
      File "<string>", line 2, in initialize
      File "/Library/Python/2.7/site-packages/IPython/config/application.py", line 92, in catch_config_error
        return method(app, *args, **kwargs)
      File "/Library/Python/2.7/site-packages/IPython/terminal/ipapp.py", line 321, in initialize
        super(TerminalIPythonApp, self).initialize(argv)
      File "<string>", line 2, in initialize
      File "/Library/Python/2.7/site-packages/IPython/config/application.py", line 92, in catch_config_error
        return method(app, *args, **kwargs)
      File "/Library/Python/2.7/site-packages/IPython/core/application.py", line 381, in initialize
        self.parse_command_line(argv)
      File "/Library/Python/2.7/site-packages/IPython/terminal/ipapp.py", line 316, in parse_command_line
        return super(TerminalIPythonApp, self).parse_command_line(argv)
      File "<string>", line 2, in parse_command_line
      File "/Library/Python/2.7/site-packages/IPython/config/application.py", line 92, in catch_config_error
        return method(app, *args, **kwargs)
      File "/Library/Python/2.7/site-packages/IPython/config/application.py", line 475, in parse_command_line
        return self.initialize_subcommand(subc, subargv)
      File "<string>", line 2, in initialize_subcommand
      File "/Library/Python/2.7/site-packages/IPython/config/application.py", line 92, in catch_config_error
        return method(app, *args, **kwargs)
      File "/Library/Python/2.7/site-packages/IPython/config/application.py", line 406, in initialize_subcommand
        subapp = import_item(subapp)
      File "/Library/Python/2.7/site-packages/IPython/utils/importstring.py", line 42, in import_item
        module = __import__(package, fromlist=[obj])
      File "/Library/Python/2.7/site-packages/IPython/html/notebookapp.py", line 42, in <module>
        from jinja2 import Environment, FileSystemLoader
    ImportError: No module named jinja2
    

I tried also to uninstall and re-install jinja2, but nothing changes. Any
suggestion?

In addition:

`mattia:~ mattiaspeziali$ which python /usr/local/bin/python`

`mattia:~ mattiaspeziali$ which ipython /usr/local/bin/ipython`

`mattia:~ mattiaspeziali$ which pip /usr/local/bin/pip`


Answer: Re-installing iPython solved the issue.

