Python recursive function改错

老师让我找错，有好心人能指导一下么。感激不尽

def count_users(group):
  count = 0
  for member in get_members(group):
    count += 1
    if is_group(member):
      count += count_users(member)
  return count

print(count_users("sales")) # Should be 3
print(count_users("engineering")) # Should be 8
print(count_users("everyone")) # Should be 18

你这有两个自定义 函数没给出了啊..