Add attachment on Blanket Purchase Agreement through RESTAPI or any other services

Summary:

Hi Team,
We are planning to migrate around 30000 BPA's using FBDI and then planning to add Clauses as a attachment.
Can you please let me know if it is possible to add attachments on Incomplete/Open Blanket Purchase Agreements though RESTAPI/Services? If Yes, then please let me know the process.

Content (please ensure you mask any confidential information):

NA

Version (include the version you are using, if applicable):

25A (11.13.25.01.0)

Code Snippet (add any code snippets that support your topic, if applicable):

NA