The reference is the event reference not the entity reference.
I have released a new version 1.5.6 which has an API call to convert the event ref to the entity ref 'entity_from_event'
If you update your version of pyPreservica using PIP you should get the new method.
from pyPreservica import *
logging.basicConfig(level=logging.FATAL)
client = EntityAPI()
for ingest_event in client.all_ingest_events(previous_days=14):
event_ref = ingest_event['Ref']
for ref in client.entity_from_event(event_ref):
try:
asset = client.asset(ref)
print(asset)
except ReferenceNotFoundException:
# The ref is a not an Asset
# It will be a Content Object or Folder
pass