How to import routes from another file in Flask – no frontend or view library solutions please, lightweight solution for Flask backend only

# file: other_routes

def init_views(app):
    @app.route("/v1/overview")
    def overview():
        ...

from flask import Flask, jsonify
from other_routes import init_views

app = Flask(__name__)
init_views(app)

from flask import Blueprint

other_routes = Blueprint("other_routes", __name__)

@other_routes.route("/v1/overview")
def overview():
    ...

from flask import Flask, jsonify
from other_routes import other_routes

app = Flask(__name__)
app.register_blueprint(other_routes)