text: from numpy import *
  from PIL import Image
  
  flag = Image.open(r"flag.png")
  img = array(flag)
  
  key = [41, 37, 23]
  
  a, b, c = img.shape
  
  for x in range (0, a):
      for y in range (0, b):
          pixel = img[x, y]
          for i in range(0,3):
              pixel[i] = pixel[i] * key[i] % 251
          img[x][y] = pixel
  
  enc = Image.fromarray(img)
  enc.save('enc.png')
  