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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 search_stresses(pattern):
 """Get words whose stress pattern matches a regular expression. This function is a special case of :func:`search` that searches only the stress patterns of each pronunciation in the dictionary. You can get stress patterns for a word using the :func:`stresses_for_word` function. .. doctest:: ['gubernatorial'] :param pattern: a string containing a regular expression :returns: a list of matching words """

    init_cmu()
    regexp = re.compile(pattern)
    return [word
            for word, phones in pronunciations
            if regexp.search(stresses(phones))]