How to use keepalive correctly?

```
import etcd3
import time
from threading import Thread

def keeper():
client = etcd3.client(host="xx.xxx.xxx.xx", port=2379)
lease = client.lease(ttl=10)
lease.refresh()
client.put('test_key', 'test_keeper', lease=lease.id)
print("lease_id", lease.id)

if __name__ == "__main__":
etcd_keeper = Thread(
target=keeper(), daemon=True)
etcd_keeper.start()
etcd_keeper.join()
time.sleep(300)
```

According to the code, i think refresh() is used for KeepAlive(), but I found that the key expires soon, anyone can advise what's wrong? Thanks``

Start by running the supplied Python snippet with the 10-second lease and observe when the key expires. Read the python-etcd3 lease and threading usage around refresh(), then compare the documented behavior with this example; done means reproducing the expiration and documenting the cause and expected usage.

Written by the indexing model from the issue text.