import requests  # because using urllib2 is like pulling teeth
import mimetypes # so we can get the file extension correct

# request a random image (will result in a 302 redirect)
random_response = requests.head("http://imgur.com/random")

# parse the filename out of the location header
filename = random_response.headers["location"].split("/")[-1]

# request the actual image
image = requests.get("http://i.imgur.com/{0}.png".format(filename))

# figure out what the file extension should be
extension = mimetypes.guess_all_extensions(image.headers['content-type'])[-1]

# write file to disk
with open("{0}{1}".format(filename, extension), "w") as f:
    f.write(image.content)