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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 distance(self, x, y):
 """ Computes the Manhattan distance between vectors x and y. Returns float. """

        if scipy.sparse.issparse(x):
            return numpy.sum(numpy.absolute((x-y).toarray().ravel()))
        else:
            return numpy.sum(numpy.absolute(x-y))