コード：

#!/usr/bin/env python
#coding: utf-8
userid="**************@gmail.com"
passwd="*******"
import sys, re, cgi, urllib, urllib.request, urllib.error, http.cookiejar, xml.dom.minidom, time, urllib.parse
import simplejson as json

def getToken():
html = urllib.request.urlopen("http://www.nicovideo.jp/my/mylist").read()
for line in html.splitlines():
    mo = re.match(r'^\s*NicoAPI\.token = "(?P<token>[\d\w-]+)";\s*',line)
    if mo:
        token = mo.group('token')
        break
assert token
return token

def mylist_create(name):
    cmdurl = "http://www.nicovideo.jp/api/mylistgroup/add"
    q = {}
    q['name'] = name.encode("utf-8")
    q['description'] = ""
    q['public'] = 0
    q['default_sort'] = 0
    q['icon_id'] = 0
    q['token'] = token
    cmdurl += "?" + urllib.parse.urlencode(q).encode("utf-8")
    j = json.load( urllib.request.urlopen(cmdurl), encoding='utf-8')
    return j['id']

def addvideo_tomylist(mid,smids):
    for smid in smids:
        cmdurl = "http://www.nicovideo.jp/api/mylist/add"
        q = {}
        q['group_id'] = mid
        q['item_type'] = 0
        q['item_id'] = smid
        q['description'] = u""
        q['token'] = token
        cmdurl += "?" + urllib.parse.urlencode(q).encode("utf-8")
        j = json.load( urllib.request.urlopen(cmdurl), encoding='utf-8')
        time.sleep(0.5)

#ログイン
opener = urllib.request.build_opener(urllib.request.HTTPCookieProcessor(http.cookiejar.CookieJar()))
urllib.request.install_opener(opener)
urllib.request.urlopen("https://secure.nicovideo.jp/secure/login",
     urllib.parse.urlencode( {"mail":userid, "password":passwd} ))
#トークン取得
token = getToken()
#マイリストの作成と動画の登録
mid = mylist_create(u"テストリスト")
addvideo_tomylist(mid, ["sm9","sm1097445", "sm1715919"  ] )

エラー：

Traceback (most recent call last):
  File "Nico3.py", line 47, in <module>
    urllib.request.urlopen("https://secure.nicovideo.jp/secure/login", urllib.parse.urlencode( {"mail":userid, "password":passwd} ))
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/urllib/request.py", line 162, in urlopen
return opener.open(url, data, timeout)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/urllib/request.py", line 463, in open
req = meth(req)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/urllib/request.py", line 1170, in do_request_
raise TypeError(msg)
TypeError: POST data should be bytes or an iterable of bytes. It cannot be of type str.

エラー２（追記）

Traceback (most recent call last):
  File "Nico3.py", line 50, in <module>
token = getToken()
  File "Nico3.py", line 11, in getToken
mo = re.match(r'^\s*NicoAPI\.token = "(?P<token>[\d\w-]+)";\s*',line)
  File "/Users/NanjoHiroki/.virtualenvs/uec/lib/python3.5/re.py", line 163, in match
return _compile(pattern, flags).match(string)
TypeError: cannot use a string pattern on a bytes-like object

エラー３：

Traceback (most recent call last):
  File "Nico3.py", line 50, in <module>
token = getToken()
  File "Nico3.py", line 15, in getToken
assert token
UnboundLocalError: local variable 'token' referenced before assignment