Sending a group notification on addition of a new member in Yowsup

Question

When I create a group and add a new member(the number of the newly added member is the number which is used to login to yowsup), I want to send a notification to all the members saying "Hello!". This reply should be automated. How do I do this?

I added a function in the file demos/cli/layer.py

def createGroupMessage(self, groupID,messageBody):
    groupID = groupID + "@g.us" 
    outgoingMessageProtocolEntity = TextMessageProtocolEntity(
    messageBody,
    to = groupID
    )
    print outgoingMessageProtocolEntity
    self.toLower(outgoingMessageProtocolEntity)

I am trying to call this in the file layers/ protocol_groups/protocolentities/notification_groups_create.py after doing the necessary imports:

def init(self, id, from, timestamp, notify, participant, offline,
    createType, groupId, creationTimestamp, creatorJid,
    subject, subjectTime, subjectOwnerJid,
    participants):
    super(CreateGroupsNotificationProtocolEntity, self).__init(_id, _from, timestamp, notify, participant, offline)
    self.setGroupProps(createType, groupId, creationTimestamp, creatorJid, subject, subjectTime, subjectOwnerJid, participants)
    self.foo1 = YowsupCliLayer()
    self.foo1.createGroupMessage(groupId,"Hello !\n")

Although the code gives no error, I don't get any message when I add the yowsup number.

The output I get is:

Message:
ID: 1442859669-5
To: 919xxxxxx515-1442843444@g.us
Type:  text
Timestamp: 1442859669
Body: Hello !!


Printing notification..
w:gp2

Notification: Notification
From: 919xxxxxx515-1442843444@g.us
Type: w:gp2
Participant: 919xxxxxx515@s.whatsapp.net
Creator: 919xxxxxx515@s.whatsapp.net
Create type: None
Creation timestamp: 1442843444
Subject: FBI
Subject owner: 919xxxxxx515@s.whatsapp.net
Subject timestamp: 1442843444
Participants: {'919xxxxxx515@s.whatsapp.net': 'admin', '91886xxxxx5@s.whatsapp.net': None}

Please let me know where am I going wrong or how can I solve this? Thanks!