<s>[INST] import os
import datetime

from flask import Flask, request
from flask_sqlalchemy import SQLAlchemy
from flask_marshmallow import Marshmallow
from flask_cors import CORS

from config import *

app = Flask(__name__)
app.config.from_object('config.Config')

db = SQLAlchemy(app)
ma = Marshmallow(app)

CORS(app)

from app import routes, models

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

**How does this code create and configures a Flask app?[/INST]