How to use the amuse.ext.bridge.bridge function in amuse

cluster = Hermite(converter, parameters=[("epsilon_squared", (0.01 | units.parsec)**2)], channel_type='sockets')

    # create the external potential of the Galaxy
    galaxy = Agama(converter, type="Dehnen", gamma=1.8, \
        rscale=1000.| units.parsec, mass=1.6e10 | units.MSun, channel_type='sockets')

    # shift the cluster to an orbit around Galactic center
    acc,_,_ = galaxy.get_gravity_at_point(0|units.kpc, Rinit, 0|units.kpc, 0|units.kpc)
    vcirc = (-acc * Rinit)**0.5
    print("Vcirc=%f km/s" % vcirc.value_in(units.kms))
    particles.x  += Rinit
    particles.vy += vcirc
    cluster.particles.add_particles(particles)

    # set up bridge; cluster is evolved under influence of the galaxy
    sys = bridge(verbose=False)
    sys.add_system(cluster, (galaxy,), False)

    # evolve and make plots
    times = units.Myr([0.,0.2,0.4,0.6,0.8,1.0,1.2,1.4])
    f = pyplot.figure(figsize=(16,8))

    for i,t in enumerate(times):
        sys.evolve_model(t, timestep=timestep)
        print("Evolved the system to time %f Myr" % t.value_in(units.Myr))

        x=sys.particles.x.value_in(units.parsec)
        y=sys.particles.y.value_in(units.parsec)

        subplot=f.add_subplot(2,4,i+1)
        subplot.plot(x,y,'r .')
        subplot.plot([0.],[0.],'b +')