'Create a fake backend communication factory.
The xg-tools creates a Concerto connection object (for V7000
devices) and returns it for use on a call to vmemclient.open().'

@mock.patch('vmemclient.open')
def setup_mock_client(self, _m_client, m_conf=None):

    _m_concerto = mock.Mock(name='Concerto', version='1.1.1', spec=vmemclient.mock_client_conf)
    if m_conf:
        _m_concerto.configure_mock(**m_conf)
    _m_client.return_value = _m_concerto
    return _m_client
