def __contains_kevin_bacon__(tweet):
    """
    Check if a tweet contains Kevin Bacon, Kevin_Bacon, or KevinBacon (case
    insensitive).

    Args:
        tweet: tweet text

    Return:
        True if the tweet text contains a form of "Kevin Bacon"

    """
    tweet_text = tweet.lower()
    if "kevin bacon" in tweet_text:
        return True
    if "kevin_bacon" in tweet_text:
        return True
    if "kevinbacon" in tweet_text:
        return True
    return False