user_agent = {'Referer':
    'https://docs.google.com/forms/d/152CTd4VY9pRvLfeACOf6SmmtFAp1CL750Sx72Rh6HJ8/viewform'
    , 'User-Agent':
    'Mozilla/5.0 (X11; Linux i686) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/28.0.1500.52 Safari/537.36'
    }
r = requests.post(url, data=form_data, headers=user_agent)
Google-Forms response with Python?