code: def create_git_action_for_new_study(self, new_study_id=None):
          
          ga = self.create_git_action()
          if new_study_id is None:
              new_study_id = self._mint_new_study_id()
          self.register_doc_id(ga, new_study_id)
          return ga, new_study_id
docs: Checks out master branch as a side effect