A relevant snippet:


                input.send_keys(x)
                ac = webdriver.ActionChains(driver)
                ac.key_down(webdriver.common.keys.Keys.SHIFT)
                ac.send_keys('\n')
                ac.key_up(webdriver.common.keys.Keys.SHIFT)
                print "hi"
                ac.perform()
                print "hello, world"

The perform() causes a weird exception to be thrown in Selenium.

Traceback (most recent call last):
  File "make_demo.py", line 51, in mkdemo
    ac.perform()
  File "/Library/Python/2.6/site-packages/selenium/webdriver/common/action_chains.py", line 35, in perform
    action()
  File "/Library/Python/2.6/site-packages/selenium/webdriver/common/action_chains.py", line 117, in <lambda>
    "isdown": True}))
  File "/Library/Python/2.6/site-packages/selenium/webdriver/remote/webdriver.py", line 144, in execute
    self.error_handler.check_response(response)
  File "/Library/Python/2.6/site-packages/selenium/webdriver/remote/errorhandler.py", line 100, in check_response
    raise exception_class(value)
WebDriverException: Message: '{"status":405,"value":["GET","HEAD","DELETE"]}'