text: from flask import render_template
  from app import app, db
  
  @app.errorhandler(404)
  def not_found_error(error):
      return render_template('404.html'), 404
  
  @app.errorhandler(500)
  def internal_error(error):
      db.session.rollback()
      return render_template('500.html'), 500
  
  @app.errorhandler(401)
  def not_authorized_error(error):
      return render_template('401.html'), 401