Traceback (most recent call last):
  File "create_group.py", line 50, in <module>
    main()
  File "create_group.py", line 45, in main
    server.groups.add_user(group, new_user._id)
  File "/Library/Python/2.7/site-packages/tableauserverclient/server/endpoint/groups_endpoint.py", line 70, in add_user
    user_set.add(new_user)
AttributeError: 'list' object has no attribute 'add'

####
# This script demonstrates how to create groups using the Tableau
# Server Client.
#
# To run the script, you must have installed Python 2.7.9 or later.
####


import argparse
import getpass
import logging

from datetime import time

import tableauserverclient as TSC


def main():

    parser = argparse.ArgumentParser(description='Creates groups and add a user to it.')
    parser.add_argument('--server', '-s', required=True, help='server address')
    parser.add_argument('--username', '-u', required=True, help='username to sign into server')
    parser.add_argument('--group', '-g', required=True, help='group to create')
    parser.add_argument('--user-to-add', '-ua', required=True, help='user to add')
    parser.add_argument('--logging-level', '-l', choices=['debug', 'info', 'error'], default='error',
                        help='desired logging level (set to error by default)')
    args = parser.parse_args()

    password = getpass.getpass("Password: ")

    # Set logging level based on user input, or error by default
    logging_level = getattr(logging, args.logging_level.upper())
    logging.basicConfig(level=logging_level)

    tableau_auth = TSC.TableauAuth(args.username, password)
    server = TSC.Server(args.server)
    with server.auth.sign_in(tableau_auth):
        group = TSC.GroupItem(args.group)
        group = server.groups.create(group)
        print("Created group {0} with ID: {1}".format(group.name, group._id))
        server.groups.populate_users(group)
        new_user = TSC.UserItem(name=args.user_to_add, site_role='Interactor')
        new_user = server.users.add(new_user)
        print("added {0} with ID: {1}".format(new_user.name, new_user._id))
        server.groups.add_user(group, new_user._id)
        print("added {0} to group {2}".format(new_user.name, group.name))

if __name__ == '__main__':
    main()