For a deeper look into our Eikon Data API, look into:
Overview | Quickstart | Documentation | Downloads | Tutorials | Articles
Yes if you use explicitly set full timestamps, e.g. '2016-01-20T15:04:05'. If you use just the date, add one day to date_from, as 2016-01-20 is interpreted as 2016-01-20T00:00:00 rather than 2016-01-20T23:59:59