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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 compute( self ):

 # compute the intersection graph into @xsections dictionary
 wordlist = self.wordlist
 """ build a dictionary of words, and their intersections """

        xsections = {}
        for i in range(len(wordlist)):
            word_i = wordlist[i]
            for j in range(len(wordlist)):
                word_j = wordlist[j]
                if i == j:
                    # force self-intersection to be 0
                    if not xsections.get(word_i,None):
                        xsections[word_i] = ['']
                    else:
                        xsections[word_i].extend([''])
                    continue
                # optimize for, i > j, info is calculated already 
                if i > j:
                    xsec_counts = xsections[word_j][i]
                else:
                    xsec_counts = tamil.utf8.word_intersection( word_i, word_j )
                if not xsections.get(word_i,None):
                    xsections[word_i] =  [xsec_counts]
                else:
                    xsections[word_i].extend( [ xsec_counts ] )
        self.xsections = xsections