from django.http import HttpResponseRedirect

def check_allowed(view_func):
    
        def _view(request, *args, **kwargs):

            request.ensemble_id = request.session.get('ensemble')

            if request.ensemble_id is None:
                return HttpResponseRedirect('/register')

            return view_func(request, *args, **kwargs)

        _view.__name__ = view_func.__name__
        _view.__dict__ = view_func.__dict__
        _view.__doc__ = view_func.__doc__

        return _view