Bot cant send message

[nggary]

I have modify the receive message part, so it can send message after message is received:

def fb_receive_message():
message_entries = json.loads(request.data.decode('utf8'))['entry']
for entry in message_entries:
for message in entry['messaging']:
if message.get('message'):
print("{sender[id]} says {message[text]}".format(**message))
client = Messager("Access code of page")
recipient_id = message['recipient']['id']
client.send_text(recipient_id, "Hello, I'm enginebai.")
return "Hi"

The access token is generated according to the tutorial image: https://cdn-images-1.medium.com/max/1600/1*op5S9F_-vsBv7FLrd4mv1g.png

In message.py line 219 req show http 400 error

[nggary]

I figure it out myself:
Change recipient_id = message['recipient']['id'] to
recipient_id = message['sender']['id']

In message.py, URL_BASE = "https://graph.facebook.com/v2.9/me/"
make sure all the post_url is not 404

[nggary]

I reopen this because I think the author may want to modify the sender example and message.py