old_contents: # -*- coding: utf-8 -*-
  
  from flask.ext.mail import Message
  from app import app, mail
  from .decorators import async
  
  
  @async
  def send_async_email(app, msg):
      with app.app_context():
          mail.send(msg)
  
  
  def send_email(subject, sender, recipients, text_body):
      msg = Message(subject, sender=sender, recipients=recipients)
      msg.body = text_body
      send_async_email(app, msg)
  
new_contents: # -*- coding: utf-8 -*-
  
  from flask_mail import Message
  from app import app, mail
  from .decorators import async
  
  
  @async
  def send_async_email(app, msg):
      with app.app_context():
          mail.send(msg)
  
  
  def send_email(subject, sender, recipients, text_body):
      msg = Message(subject, sender=sender, recipients=recipients)
      msg.body = text_body
      send_async_email(app, msg)
  
subject: Update helper.py