python-读取文件行并将其放入数组中

我得到了以下代码

#!/usr/bin/python
from twitter import *

OAUTH_TOKEN = 'my oauth token'
OAUTH_SECRET = 'my oauth secret'
CONSUMER_KEY = 'my consumer key'
CONSUMER_SECRET = 'my consumer secret'

USERNAME =  "my username"
LIST_NAME = "fud"

def main():

  twitter = Twitter(api_version='1.1', auth=OAuth(OAUTH_TOKEN, OAUTH_SECRET, CONSUMER_KEY,     CONSUMER_SECRET))
  try:

    # view a users lists
    lists = twitter.lists.list(user=USERNAME)
    # create a list
    create_list = twitter.lists.create(name=LIST_NAME)
    # view list members
    list_members = twitter.lists.members(slug=LIST_NAME, owner_screen_name=USERNAME)
    # add single user to list
    twitter.lists.members.create(owner_screen_name=USERNAME, slug=LIST_NAME, screen_name="microsoft")

    # add multiple users to list 
    twitter.lists.members.create_all(owner_screen_name=USERNAME, slug=LIST_NAME, screen_name="twitter,python")


  except TwitterHTTPError as twerr:
    import zlib
    print twerr, zlib.decompress(twerr.response_data, 16+zlib.MAX_WBITS) # gunzip response error info 

main()

在代码的这一部分

    twitter.lists.members.create_all(owner_screen_name=USERNAME, slug=LIST_NAME, screen_name="twitter,python")

如何用文件中的值替换screen_name=“twitter，python”值，如读取screennames.txt行并放置所有值screen_name=“values，values..等”

请建议

I获取：文件“twitter.py”，第28行屏幕名称='，'。加入（map（str.rstrip，namefile.readlines（））^IndentationError:应为缩进块

with open('screennames.txt') as namefile:
    screennames = ','.join(map(str.rstrip, namefile.readlines()))