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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 random_sense(ambiguous_word: str, pos=None) -> "wn.Synset": """ Returns a random sense. :param ambiguous_word: String, a single word. :param pos: String, one of 'a', 'r', 's', 'n', 'v', or None. :return: A random Synset. """


    if pos is None:
        return custom_random.choice(wn.synsets(ambiguous_word))
    else:
        return custom_random.choice(wn.synsets(ambiguous_word, pos))