Flaskで任意の関数を呼び出す方法

from flask import Flask, render_template, redirect, url_for

app = Flask(__name__)

def hoge_app():
    ***何かしらの処理***

@app.route('/')
def top_page():
    return render_template('index.html')

@app.route('/hoge')
def hoge():
    hoge_app()
    return redirect(url_for('top\_page'))


if __name__ == "__main__":
    app.run('0.0.0.0', debug=True)