curl --request POST \
  --url https://api.example.com/v2/email-threads/{email_thread_id}/emails/{email_id}/invoices/{invoice_id}/pdf/presign \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "filename": "<string>"
}
'

{
  "attachment": {
    "created_at": "2023-11-07T05:31:56Z",
    "modified_at": "2023-11-07T05:31:56Z",
    "id": "<string>",
    "name": "<string>",
    "mime_type": "<string>",
    "size": 123,
    "is_verified": true,
    "object": "<string>"
  },
  "presigned_url": {
    "url": "<string>",
    "fields": {}
  }
}