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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 ycbcr2rgb(y__, cb_, cr_):
 """Convert the three YCbCr channels to RGB channels. """


    kb_ = 0.114
    kr_ = 0.299

    r__ = 2 * cr_ / (1 - kr_) + y__
    b__ = 2 * cb_ / (1 - kb_) + y__
    g__ = (y__ - kr_ * r__ - kb_ * b__) / (1 - kr_ - kb_)

    return r__, g__, b__