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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 diff_levenshtein(self, diffs):
 """Compute the Levenshtein distance; the number of inserted, deleted or substituted characters. Args: diffs: Array of diff tuples. Returns: Number of changes. """

    levenshtein = 0
    insertions = 0
    deletions = 0
    for (op, data) in diffs:
      if op == self.DIFF_INSERT:
        insertions += len(data)
      elif op == self.DIFF_DELETE:
        deletions += len(data)
      elif op == self.DIFF_EQUAL:
        # A deletion and an insertion is one substitution.
        levenshtein += max(insertions, deletions)
        insertions = 0
        deletions = 0
    levenshtein += max(insertions, deletions)
    return levenshtein