title: Multiple incompatible subclass instances of InteractiveShellEmbed are being created
body: <p>If I install the <a href="http://docs.continuum.io/anaconda/">Anaconda Python Distribution</a> and try to run <code>ipython manage.py shell</code> from within my django app, the error below is thrown. I know that when I install anaconda, it comes packaged with python and ipython whose version differs from the other python/ipython versions I have. But irrespective of the ipython version, why should the django shell throw an error? I tried uninstalling the system ipython and the same error gets thrown, which implies that there is some issue with the anaconda ipython distribution and django. Uninstalling anaconda solves the problem. </p>
  
  <p>Stacktrace</p>
  
  <pre><code>manage.py in &lt;module&gt;()
        9 
       10 if __name__ == "__main__":
  ---&gt; 11     execute_manager(settings)
  
  lib/python2.7/site-packages/django/core/management/__init__.pyc in execute_manager(settings_mod, argv)
      457     setup_environ(settings_mod)
      458     utility = ManagementUtility(argv)
  --&gt; 459     utility.execute()
  
  lib/python2.7/site-packages/django/core/management/__init__.pyc in execute(self)
      380             sys.stdout.write(self.main_help_text() + '\n')
      381         else:
  --&gt; 382             self.fetch_command(subcommand).run_from_argv(self.argv)
      383 
      384 def setup_environ(settings_mod, original_settings_path=None):
  
  lib/python2.7/site-packages/django/core/management/base.pyc in run_from_argv(self, argv)
      194         options, args = parser.parse_args(argv[2:])
      195         handle_default_options(options)
  --&gt; 196         self.execute(*args, **options.__dict__)
      197 
      198     def execute(self, *args, **options):
  
  lib/python2.7/site-packages/django/core/management/base.pyc in execute(self, *args, **options)
      230             if self.requires_model_validation:
      231                 self.validate()
  --&gt; 232             output = self.handle(*args, **options)
      233             if output:
      234                 if self.output_transaction:
  
  lib/python2.7/site-packages/django/core/management/base.pyc in handle(self, *args, **options)
      369         if args:
      370             raise CommandError("Command doesn't accept any arguments")
  --&gt; 371         return self.handle_noargs(**options)
      372 
      373     def handle_noargs(self, **options):
  
  lib/python2.7/site-packages/django_extensions/management/commands/shell_plus.pyc in handle_noargs(self, **options)
      116                 try:
      117                     from IPython import embed
  --&gt; 118                     embed(user_ns=imported_objects)
      119                 except ImportError:
      120                     # IPython &lt; 0.11
  
  lib/python2.7/site-packages/IPython/terminal/embed.pyc in embed(**kwargs)
      298         config.InteractiveShellEmbed = config.TerminalInteractiveShell
      299         kwargs['config'] = config
  --&gt; 300     shell = InteractiveShellEmbed.instance(**kwargs)
      301     shell(header=header, stack_depth=2, compile_flags=compile_flags)
  
  lib/python2.7/site-packages/IPython/config/configurable.pyc in instance(cls, *args, **kwargs)
      358             raise MultipleInstanceError(
      359                 'Multiple incompatible subclass instances of '
  --&gt; 360                 '%s are being created.' % cls.__name__
      361             )
      362 
  
  MultipleInstanceError: Multiple incompatible subclass instances of InteractiveShellEmbed are being created.
  </code></pre>