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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 projection_as_vec_v3(v, w):
 """Return the signed length of the projection of vector v on vector w. Returns the full vector result of projection_v3(). """

    proj_len = projection_v3(v, w)
    return scale_v3(v, proj_len)