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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(v, w):
 """ cross product of two vectors """

    x = v[1] * w[2] - v[2] * w[1]
    y = v[2] * w[0] - v[0] * w[2]
    z = v[0] * w[1] - v[1] * w[0]
    return [x, y, z]