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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 positions(self, word):
 """ Returns a list of positions where the word can be hyphenated. See also Hyph_dict.positions. The points that are too far to the left or right are removed. """

        right = len(word) - self.right
        return [i for i in self.hd.positions(word) if self.left <= i <= right]