code: def get_dependencies(self, item):
          
          def _get_sub_dependency(sub_item):
              e = self._deps.get(sub_item)
              if e is None:
                  return self.get_default()
  
              if e.dependencies is NotInitialized:
                  e.dependencies = self.merge_dependency(sub_item, _get_sub_dependency, e.parent)
              return e.dependencies
  
          return _get_sub_dependency(item)
docs: Performs a dependency check on the given item.
  
          :param item: Node to start the dependency check with.
          :return: The result on merged dependencies down the hierarchy.