curl --location --request POST 'https://api.baichuan-ai.com/v1/files/' \
--header 'Authorization: Bearer $API_KEY'                {
  "id": "file-abc123",
  "object": "file",
  "bytes": 120000,
  "created_at": 1677610602,
  "filename": "mydata.pdf",
  "purpose": "knowledge-base"
}