Sentry test message failed by raven , but worked for python-sdk

I create a test project , it’s not working by maven in python 2.7

from raven import Client

client = Client('https://xxxxxxxx@sentryxxxx.com/6')

try:
    1 / 0
except ZeroDivisionError:
    client.captureException()

Sentry is attempting to send 1 pending error messages

Waiting up to 10 seconds

Press Ctrl-Break to quit

No handlers could be found for logger “sentry.errors”

It showed no events in project .

but worked with sentry-sdk:

import sentry_sdk

sentry_sdk.init("https://<key>@sentry.io/<project>")

from sentry_sdk import capture_message

capture_message('Something went wrong')

It showed a new event in project .

What caused this problem ?