new tests for iterator

• reach 100% coverage for data_handler/iterator.py

changed milestone to %Improve Test Coverage

added To Do label

changed time estimate to 30m

added Doing label and removed To Do label

assigned to @leufen1

created merge request !216 (merged) to address this issue

mentioned in merge request !216 (merged)

mentioned in commit 18a7c5e7

marked the checklist item reach 100% coverage for data_handler/iterator.py as completed

added 1h 39m of time spent at 2020-12-17

added .done label and removed Doing label

added merged in Develop label and removed .done label

mentioned in commit 82c83089

closed with commit 82c83089

closed with commit 18a7c5e7

mentioned in commit cf6bca9d

closed with merge request !225 (merged)