code: def add_child_objective_bank(self, objective_bank_id, child_id):
          
          # Implemented from template for
          # osid.resource.BinHierarchyDesignSession.add_child_bin_template
          if self._catalog_session is not None:
              return self._catalog_session.add_child_catalog(catalog_id=objective_bank_id, child_id=child_id)
          return self._hierarchy_session.add_child(id_=objective_bank_id, child_id=child_id)
docs: Adds a child to an objective bank.
  
          arg:    objective_bank_id (osid.id.Id): the ``Id`` of an
                  objective bank
          arg:    child_id (osid.id.Id): the ``Id`` of the new child
          raise:  AlreadyExists - ``objective_bank_id`` is already a
                  parent of ``child_id``
          raise:  NotFound - ``objective_bank_id`` or ``child_id`` not
                  found
          raise:  NullArgument - ``objective_bank_id`` or ``child_id`` is
                  ``null``
          raise:  OperationFailed - unable to complete request
          raise:  PermissionDenied - authorization failure
          *compliance: mandatory -- This method must be implemented.*