server.py

from flask import Flask

app = Flask(__name__)
app.config["SERVER_NAME"] = "flaskapp.local:5000"


@app.route("/")
def root_index():
    return "this is flaskapp.local"


@app.route("/", subdomain="<vehicle>")
def subdomain_index(vehicle):
    return vehicle


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