How to use the strsimpy.string_distance.MetricStringDistance function in strsimpy

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from .string_distance import MetricStringDistance


class Levenshtein(MetricStringDistance):

    def distance(self, s0, s1):
        if s0 is None:
            raise TypeError("Argument s0 is NoneType.")
        if s1 is None:
            raise TypeError("Argument s1 is NoneType.")
        if s0 == s1:
            return 0.0
        if len(s0) == 0:
            return len(s1)
        if len(s1) == 0:
            return len(s0)

        v0 = [0] * (len(s1) + 1)
        v1 = [0] * (len(s1) + 1)