refactored app structure

app/email.py

@@ -0,0 +1,23 @@
+import threading
+
+from flask import current_app, render_template
+from flask_mail import Message
+
+from app import mail, config
+
+
+def send_async_email(app, msg):
+    with app.app_context():
+        mail.send(msg)
+
+def send_email(to, subject, template, **kwargs):
+    msg = Message(
+        
+        current_app.config['MAIL_PREFIX'] + subject,
+        sender=current_app.config['MAIL_SENDER'], recipients=to)
+    msg.body = render_template(template + '.txt', **kwargs)
+    msg.html = render_template(template + '.html', **kwargs)
+    
+    mail_thread = threading.Thread(target=send_async_email, args=[current_app._get_current_object(), msg])
+    mail_thread.start()
+    return mail_thread