Get more than 100 usernames from a slack channel

channel_username.py

import os
import requests

SLACK_API_TOKEN='' # Your token here
FROM_CHANNEL_ID='' # Get the id from the bottom of the channel description
NEW_CHANNEL_ID=''
LIMIT=200 # default limit was 100 need to change based on size

members = requests.get('https://slack.com/api/conversations.members?token=%s&channel=%s&limit=%s' % (SLACK_API_TOKEN, FROM_CHANNEL_ID, LIMIT)).json()['members']
existing_members = requests.get('https://slack.com/api/conversations.members?token=%s&channel=%s&limit=%s' % (SLACK_API_TOKEN, NEW_CHANNEL_ID, LIMIT)).json()['members']

for id in members:
    if id not in existing_members:
#         print(id)
        user = requests.get('https://slack.com/api/users.info?token=%s&user=%s' % (SLACK_API_TOKEN, id)).json()
        if user['ok']:
            print('@' + user['user']['name'])