improve: introduce isort for linting Python imports (#1983)

api/models/dataset.py

@@ -2,12 +2,11 @@ import json
 import pickle
 from json import JSONDecodeError
 
-from sqlalchemy import func
-from sqlalchemy.dialects.postgresql import UUID, JSONB
-
 from extensions.ext_database import db
 from models.account import Account
 from models.model import App, UploadFile
+from sqlalchemy import func
+from sqlalchemy.dialects.postgresql import JSONB, UUID
 
 
 class Dataset(db.Model):