old_contents: from flask import Blueprint, flash
  
  
  class Bootstrap(Blueprint):
      def __init__(self, app):
          super(Bootstrap, self).__init__(
              'bootstrap', __name__, template_folder='templates'
          )
          app.register_blueprint(self)
  
  
  def success(msg):
      flash(msg, 'success')
  
  
  def error(msg):
      flash(msg, 'error')
  
new_contents: from flask import Blueprint, flash
  
  
  class Bootstrap(Blueprint):
      def __init__(self, app):
          super(Bootstrap, self).__init__(
              'bootstrap', __name__, template_folder='templates'
          )
          app.register_blueprint(self)
  
  
  def success(msg):
      flash(msg, 'success')
  
  
  def error(msg):
      flash(msg, 'danger')
  
subject: change error flag to danger