https://dev.twitter.com/docs/api/1.1/get/lists/members
#Get a list of users and output the number of registered users
#t is a twitter class instance
hoge = t.lists.list(user_id='user_id')
for h in hoge:
print(h['name'] + ':' + h['id_str'])
cursor = '-1'
count = 0
while cursor != '0':
#cursor=-1 the first "page."
tl = t.lists.members(list_id=h['id_str'],cursor=cursor)
count += len(tl['users'])
cursor = tl['next_cursor_str'] #If there is no next page, 0 is entered
print(count)