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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_v3(vec_a, vec_b):
 """Return the crossproduct between vec_a and vec_b."""


    return Vec3(vec_a.y * vec_b.z - vec_a.z * vec_b.y,
                vec_a.z * vec_b.x - vec_a.x * vec_b.z,
                vec_a.x * vec_b.y - vec_a.y * vec_b.x)