initiate mongoengine in flask code example

Example: flask mongoengine configuration

'''Basic setup can be done by defining MONGODB_SETTINGS
on app.config and creating a MongoEngine instance.'''
from flask import Flask
from flask_mongoengine import MongoEngine

app = Flask(__name__)
app.config['MONGODB_SETTINGS'] = {
    "db": "myapp",
}
db = MongoEngine(app)