code: def lab2hcl(l__, a__, b__):
      
      l2_ = (l__ - 9) / 61.0
      r__ = np.sqrt(a__*a__ + b__*b__)
      s__ = r__ / (l2_ * 311 + 125)
      angle = np.arctan2(a__, b__)
      c__ = np.rad2deg(np.pi / 3 - angle)%360
      return c__, s__, l2_
docs: L*a*b* to HCL