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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 clean_single_word(word, lemmatizing="wordnet"):
 """ Performs stemming or lemmatizing on a single word. If we are to search for a word in a clean bag-of-words, we need to search it after the same kind of preprocessing. Inputs: - word: A string containing the source word. - lemmatizing: A string containing one of the following: "porter", "snowball" or "wordnet". Output: - lemma: The resulting clean lemma or stem. """

    if lemmatizing == "porter":
        porter = PorterStemmer()
        lemma = porter.stem(word)
    elif lemmatizing == "snowball":
        snowball = SnowballStemmer('english')
        lemma = snowball.stem(word)
    elif lemmatizing == "wordnet":
        wordnet = WordNetLemmatizer()
        lemma = wordnet.lemmatize(word)
    else:
        print("Invalid lemmatizer argument.")
        raise RuntimeError

    return lemma