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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 similarity(self, track):
 """ Compares two tracks based on their topology This method compares the given track against this instance. It only verifies if given track is close to this one, not the other way arround Args: track (:obj:`Track`) Returns: Two-tuple with global similarity between tracks and an array the similarity between segments """

        idx = index.Index()
        i = 0
        for i, segment in enumerate(self.segments):
            idx.insert(i, segment.bounds(), obj=segment)

        final_siml = []
        final_diff = []
        for i, segment in enumerate(track.segments):
            query = idx.intersection(segment.bounds(), objects=True)

            res_siml = []
            res_diff = []
            for result in query:
                siml, diff = segment_similarity(segment, result.object)
                res_siml.append(siml)
                res_diff.append((result.id, i, diff))

            if len(res_siml) > 0:
                final_siml.append(max(res_siml))
                final_diff.append(res_diff[np.argmax(res_siml)])
            else:
                final_siml.append(0)
                final_diff.append([])

        return np.mean(final_siml), final_diff