old_contents: from flask import render_template
  
  from app.main import main
  
  
  @main.app_errorhandler(403)
  def forbidden(_):
      return render_template('errors/403.html'), 403
  
  
  @main.app_errorhandler(404)
  def page_not_found(_):
      return render_template('errors/404.html'), 404
  
  
  @main.app_errorhandler(500)
  def internal_server_error(_):
      return render_template('errors/500.html'), 500
  
new_contents: from flask import render_template
  
  from app.main.views import main
  
  
  @main.app_errorhandler(403)
  def forbidden(_):
      return render_template('errors/403.html'), 403
  
  
  @main.app_errorhandler(404)
  def page_not_found(_):
      return render_template('errors/404.html'), 404
  
  
  @main.app_errorhandler(500)
  def internal_server_error(_):
      return render_template('errors/500.html'), 500
  
subject: Fix import error