If you wish to store your backups on a periodic basis,on Dropbox, you can do it directly through ERPNext.
Setup > Manage 3rd Party Backups
Step 1: Click on Integrations > Backup Manager
In the Backup Manager page, enter the email addresses of those people whom you wish to notify about the upload status. Under the topic 'Sync with Dropbox', select whether you wish to upload Daily, Weekly or Never.
Step 2 Click on Allow Dropbox Access.
Tip: In future, if you wish to discontinue uploading backups to dropbox, then select the Never option.
You need to login to your dropbox account, with your user id and password.
{
"db_name": "demo",
"db_password": "DZ1Idd55xJ9qvkHvUH",
"dropbox_access_key": "ACCESSKEY",
"dropbox_secret_key": "SECRECTKEY"
}