如何使用Flask/SqlAlchemy/SQLite对过去7天中的每一天的数据库记录进行分组？

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from datetime import datetime, timedelta

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///your_database.db'
db = SQLAlchemy(app)

class Record(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    timestamp = db.Column(db.DateTime, default=datetime.utcnow)
    data = db.Column(db.String(255))

db.create_all()

@app.route('/')
def group_records_by_day():
    today = datetime.now().date()
    week_ago = today - timedelta(days=7)
    
    records = db.session.query(Record).filter(Record.timestamp >= week_ago).all()
    
    grouped_records = {}
    for record in records:
        record_date = record.timestamp.date()
        if record_date not in grouped_records:
            grouped_records[record_date] = []
        grouped_records[record_date].append(record)
    
    return grouped_records

if __name__ == '__main__':
    app.run()