Flask

server.py

from flask import Flask
from flask import request
from json import dumps
from flask import Response

app = Flask(__name__)

messages = dict()
message_id = 0

@app.errorhandler(404)
def error_message(e):
    return '<h1>Пашел нахуй))</h1>'

@app.route('/message')
def send_message():
    global message_id
    message_id += 1

    messages.update({
        f'{message_id}' : {
            'username': request.args.get('username'),
            'text': request.args.get('text'),
            'time':request.args.get('time')
        }
    })
    messages['count'] = message_id
    return Response(dumps(messages), mimetype='application/json')

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