async def METHOD_NAME(self, mock_conn_mgr, request_context):
    mock_conn_mgr.return_value.accept_response = async_mock.CoroutineMock()
    mock_conn_mgr.return_value.accept_response.side_effect = ConnectionManagerError(
        error_code=ProblemReportReason.RESPONSE_NOT_ACCEPTED
    )
    request_context.message = ConnectionResponse()
    handler_inst = handler.ConnectionResponseHandler()
    responder = MockResponder()
    await handler_inst.handle(request_context, responder)
    messages = responder.messages
    assert len(messages) == 1
    result, target = messages[0]
    assert (
        isinstance(result, ConnectionProblemReport)
        and result.problem_code == ProblemReportReason.RESPONSE_NOT_ACCEPTED
    )
    assert target == {"target_list": None}