Python - send file with Slack API using post request

slack.py

# Send file with Slack API using post request
# Under "Add an OAuth scope" you need to add "files:write:user" permission
# https://api.slack.com/methods/files.upload#arg_title
# https://api.slack.com/types/file#file_types

def get_file_content(file_name):
    content = ''
    with open(file_name, 'rb') as f:
        content = f.read()
    return content

# Post file with slack 
def send_file():
    content = get_file_content('text.txt')
    url = "https://slack.com/api/files.upload"
    headers = {"Content-Type": "application/x-www-form-urlencoded"}
    data = {
        'token': 'xoxb-xxxx-xxxx-xxxx',
        'channels': 'xxxxxx',
        'content': content,
        'filename': 'text.txt',
        'filetype': 'text',
        'title': 'text.txt',
    }
    res = requests.post(url=url, data=data, headers=headers)
    if res.status_code == 200:
        print(f'Response: {res.json()}')
    else:
        print(f'Fail to send: {res.json()}')