The code:
report = usage_reporter.generate_report(focus='org', report_type='itemUsages', duration='weekly', start_time=target_date, notify=True, future=False)
errors with the exception "invalid timeAggregate value".
What I am trying to do is create this usage report in Python:

which does not appear to have a timeAggregate value. Also, there is no parameter in the create_report method that accounts for time aggregation.
We are trying to automate report generation.
Does anyone have a similar experience?