code: def simple_atmo(rgb, haze, contrast, bias):
      
      gamma_b = 1 - haze
      gamma_g = 1 - (haze / 3.0)
      arr = np.empty(shape=(3, rgb.shape[1], rgb.shape[2]))
  
      arr[0] = rgb[0]
      arr[1] = gamma(rgb[1], gamma_g)
      arr[2] = gamma(rgb[2], gamma_b)
  
      output = rgb.copy()
      output[0:3] = sigmoidal(arr, contrast, bias)
  
      return output
docs: A simple, static (non-adaptive) atmospheric correction function.
  
      Parameters
      ----------
      haze: float
          Amount of haze to adjust for. For example, 0.03
      contrast : integer
          Enhances the intensity differences between the lighter and darker
          elements of the image. For example, 0 is none, 3 is typical and
          20 is a lot.
      bias : float, between 0 and 1
          Threshold level for the contrast function to center on
          (typically centered at 0.5 or 50%)