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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 edit_distance_2(self, word):
 """ Compute all strings that are two edits away from `word` using only the letters in the corpus Args: word (str):
 The word for which to calculate the edit distance Returns: set: The set of strings that are edit distance two from the \ provided word """

        word = word.lower()
        return [
            e2 for e1 in self.edit_distance_1(word) for e2 in self.edit_distance_1(e1)
        ]