flask cors

$ pip install flask-cors

from flask import Flask
from flask_cors import CORS, cross_origin

app = Flask(__name__)
CORS(app)

@app.route("/")
def helloWorld():
    return "Hello world"

@app.route("/", methods=["GET"])
def get_example():
    """GET in server"""
    response = jsonify(message="Simple server is running")

    # Enable Access-Control-Allow-Origin
    response.headers.add("Access-Control-Allow-Origin", "*")
    return response