* new file *iterating_through_submasks* is added in dynamic_programming section
* no changes
* *iterating_through_submasks.py is added in dynamic_programming
* iterating_through_submasks is added with doctests
* iterating_through_submasks.py is added in dynamic_programming
* changes made in *iterating_through_submasks.py
* changes made in *iterating_through_submasks.py
* updated