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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 cross(self, vector):
 """Return a Vector instance as the cross product of two vectors"""

        return Vector((self.y * vector.z - self.z * vector.y),
                      (self.z * vector.x - self.x * vector.z),
                      (self.x * vector.y - self.y * vector.x))