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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 unify(self):
 """Unifies the vector. The length of the vector will be 1. :return: Return the instance itself :rtype: Vector """

        length = float(self.norm())
        for row in xrange(self.get_height()):
            self.set_value(0, row, self.get_value(0, row) / length)
        return self