This is to update a record named jellyfin. Its a python script.

  import json
  import requests
  
  IP_API = 'https://api.ipify.org?format=json'
  CF_API_KEY = # Cloudflare API Key
  CF_EMAIL = # Cloudflare email address
  ZONE_ID = # Zone ID
  RECORD_ID = # Record ID for this DNS entry
  
  resp = requests.get(IP_API)
  ip = resp.json()['ip']
  
  
  resp = requests.put(
      'https://api.cloudflare.com/client/v4/zones/{}/dns_records/{}'.format(
          ZONE_ID, RECORD_ID),
      json={
          'type': 'A',
          'name': 'jellyfin',
          'content': ip,
          'proxied': False
      },
      headers={
          'X-Auth-Key': CF_API_KEY,
          'X-Auth-Email': CF_EMAIL
      })