'Construct a TrigramCollocationFinder, given FreqDists for
appearances of words, bigrams, two words with any word between them,
and trigrams.'

def __init__(self, word_fd, bigram_fd, wildcard_fd, trigram_fd):

    AbstractCollocationFinder.__init__(self, word_fd, trigram_fd)
    self.wildcard_fd = wildcard_fd
    self.bigram_fd = bigram_fd
