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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 vector_similarity(self, vector, items):
 """Compute the similarity between a vector and a set of items."""

        vector = self.normalize(vector)
        items_vec = np.stack([self.norm_vectors[self.items[x]] for x in items])
        return vector.dot(items_vec.T)