code: def sigmoid_gamma(img, stateimg, alpha, beta):
      height, width, _ = img.shape
  
      c1 = 1 / (1 + np.exp(beta))
      c2 = 1 / (1 + np.exp(beta - alpha)) - c1
  
      lut = [np.uint8()] * 256
  
      # compute the lut
      for k in range(256):
          lut[k] = np.uint8(
              ((1 / (1 + np.exp(beta - (k / 255.0) * alpha))) - c1)
              * 255
              / c2
          )
      for i in range(height):
          for j in range(width):
              img[i, j, 0] = lut[stateimg[i, j, 0]]
              img[i, j, 1] = lut[stateimg[i, j, 1]]
              img[i, j, 2] = lut[stateimg[i, j, 2]]
  
file_path: pythran/pythran/tests/scikit-image/_colormixer.py
imports: import numpy
label_desc: Use image node_id 4 for calling a global function with example usage: sigmoid_gamma(img, stateimg, alpha, beta) without return types