code: def get_item_bank_assignment_session(self):
          
          if not self.supports_item_bank_assignment():
              raise errors.Unimplemented()
          # pylint: disable=no-member
          return sessions.ItemBankAssignmentSession(runtime=self._runtime)
docs: Gets the ``OsidSession`` associated with the item bank assignment service.
  
          return: (osid.assessment.ItemBankAssignmentSession) - an
                  ``ItemBankAssignmentSession``
          raise:  OperationFailed - unable to complete request
          raise:  Unimplemented - ``supports_item_bank_assignment()`` is
                  ``false``
          *compliance: optional -- This method must be implemented if
          ``supports_item_bank_assignment()`` is ``true``.*