new_contents: from collections import Counter
  
  # we've got cycles to spare, lets confirm
  
  
  def valid(s):
      counter = Counter(s)
  
      for c in counter:
          if counter[c] != 1:
              return False
  
      return True
  
  best = None
  
  for x in range(90000, 100000):
      for y in range(80000, 90000):
          if valid(str(x) + str(y)):
              if not best or (x*y) > best:
                  print(x, y, x*y)
                  best = x * yp
subject: Add brute force of knowit20