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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 start_browser_when_ready(host, port=None, cancel_event=None):
 """ Starts a thread that waits for the server then opens the specified address in the browser. Set cancel_event to cancel the wait. The started thread object is returned. """

    browser_thread = Thread(
        target=wait_and_start_browser, args=(host, port, cancel_event))
    browser_thread.daemon = True
    browser_thread.start()
    return browser_thread