Asana API Event not returning new Sync - python

Hi Team,
When we are trying to trigger the events end point using the existing sync, the response payloads contains only the DATA element. The new Sync generated is not getting returned to the calling program.

Below is the code snippet.
import asana
client = asana.Client.access_token(personal_access_token)
result = client.events.get_events(opt_fields=[“resource”,“sync”], resource=project_gid, sync=sync)

while True:
try:
resource = next(result)
if resource[‘resource’][“resource_type”] == “task”:
changed_tasks.append(resource[‘resource’][“gid”])
except StopIteration as f:
break

Please advise how to get the Sync attribute to be included in the response. Thanks in advance!