from random import randint

def niveau1():
  tirage = randint(1, 100)
  if tirage <= 60 :
    return "A"
  else:
    return "B"

def niveau2():
  etape = niveau1()
  tirage = randint(1, 100)
  if etape == "A":
    if ..........:
      return "C"
  else:
    if ..........:
      return "C"
  return "D"