new_contents: from random import randint
  
  def makeCode(length,number):
      code = []
      code_set = set(code)
      code_map = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
      limit = len(code_map)
      while(len(code_set)<number):
          this_code = ""
          for i in range(length):
              this_code += code_map[randint(0,limit-1)]
          code.append(this_code)
          code_set = set(code)
  
      return code_set
  
  
  if __name__ == '__main__':
      for i in makeCode(30,200):
          print i
subject: add solution