REF: added get_parser function
REF: added get_parser function

Former-commit-id: a7aa61193655cd60aa984dd2b6fccc565864edd3
Former-commit-id: 8e2ea13382ca2baa2dd40b50713efa5b509fc50b
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox