curl --request POST \
  --url https://api.example.com/api/playground/sessions/{session_id}/hypotheses \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "hypotheses": [
    {
      "protected_column": "<string>",
      "target_column": "<string>",
      "target_class": "<string>",
      "association": 123,
      "note": "<string>"
    }
  ]
}
'

{
  "session_id": "<string>",
  "saved": 123,
  "hypothesis_ids": [
    "<string>"
  ]
}