usage: rucio-undertaker [-h] [--run-once] [--total-workers TOTAL_WORKERS]
                        [--chunk-size CHUNK_SIZE] [--sleep-time SLEEP_TIME]
The Undertaker daemon is responsible for managing expired DIDs. It deletes DIDs, but not replicas by checking if there are DIDs where the 'expired_at' date property is older than the current timestamp.
options:
  -h, --help            show this help message and exit
  --run-once            One iteration only
  --total-workers TOTAL_WORKERS
                        Total number of workers
  --chunk-size CHUNK_SIZE
                        Chunk size
  --sleep-time SLEEP_TIME
                        Concurrency control: thread sleep time after each
                        chunk of work
Create a DID that is already expired by setting its lifetime to -1::
  $ python
  from rucio.db.sqla.constants import DIDType
  from rucio.client.didclient import DIDClient
  client = DIDClient()
  client.add_did(scope='mock', name='test', type=DIDType.DATASET, lifetime=-1)
Check if the DID exists::
  $ rucio list-dids mock:test
  +--------------+--------------+
  | SCOPE:NAME   | [DID TYPE]   |
  |--------------+--------------|
  | mock:test    | DATASET      |
  +--------------+--------------+
Run the daemon::
  $ rucio-undertaker --run-once
Check if the DID exists::
  $ rucio list-dids mock:test
  +--------------+--------------+
  | SCOPE:NAME   | [DID TYPE]   |
  |--------------+--------------|
  +--------------+--------------+