access to xmlhttprequest at from origin has been blocked by cors policy asp.net code example

Example 1: javascript access to xmlhttprequest at from origin 'null' has been blocked by cors policy

//Open the HTML file using live server, it will work

Example 2: ccess to XMLHttpRequest at 'http://127.0.0.1:5000/ has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

@app.route('your route', methods=['GET'])
def yourMethod(params):
    response = flask.jsonify({'some': 'data'})
    response.headers.add('Access-Control-Allow-Origin', '*')
    return response