code: def get_assignable_bank_ids(self, bank_id):
          
          # This will likely be overridden by an authorization adapter
          mgr = self._get_provider_manager('ASSESSMENT', local=True)
          lookup_session = mgr.get_bank_lookup_session(proxy=self._proxy)
          banks = lookup_session.get_banks()
          id_list = []
          for bank in banks:
              id_list.append(bank.get_id())
          return IdList(id_list)
docs: Gets a list of bank including and under the given bank node in which any assessment part can be assigned.
  
          arg:    bank_id (osid.id.Id): the ``Id`` of the ``Bank``
          return: (osid.id.IdList) - list of assignable bank ``Ids``
          raise:  NullArgument - ``bank_id`` is ``null``
          raise:  OperationFailed - unable to complete request
          *compliance: mandatory -- This method must be implemented.*