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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def css(request):
 """ Custom CSS for TinyMCE 4 widget By default it fixes widget's position in Django Admin :param request: Django http request :type request: django.http.request.HttpRequest :return: Django http response with CSS file for TinyMCE 4 :rtype: django.http.HttpResponse """

    if 'grappelli' in settings.INSTALLED_APPS:
        margin_left = 0
    elif VERSION[:2] <= (1, 8):
        margin_left = 110  # For old style admin
    else:
        margin_left = 170  # For Django >= 1.9 style admin
    # For Django >= 2.0 responsive admin
    responsive_admin = VERSION[:2] >= (2, 0)
    return HttpResponse(render_to_string('tinymce/tinymce4.css',
                                         context={
                                             'margin_left': margin_left,
                                             'responsive_admin': responsive_admin
                                         },
                                         request=request),
                        content_type='text/css; charset=utf-8')