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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_distance_fast(self):
 """Calls edit_distance, and asserts that if we already have values for matches and distance, that they match."""

        d, m = edit_distance(self.seq1, self.seq2,
                             action_function=self.action_function,
                             test=self.test)
        if self.dist:
            assert d == self.dist
        if self._matches:
            assert m == self._matches
        self.dist = d
        self._matches = m