backend_cfg = habitat_sim.SimulatorConfiguration()
    backend_cfg.scene.id = (
        "~sorted_faces/sorted_faces_apartment_0")  

    hfov = 2 * math.degrees(math.atan(width / (2 * cam_focalLength)))
    vfov = 2 * math.degrees(math.atan(height / (2 * cam_focalLength)))
    # First, let's create a stereo RGB agent
    left_rgb_sensor = habitat_sim.SensorSpec()
    # Give it the uuid of left_sensor, this will also be how we
    # index the observations to retrieve the rendering from this sensor
    left_rgb_sensor.uuid = "left_sensor"
    left_rgb_sensor.resolution = [height, width]
    left_rgb_sensor.parameters["hfov"] = str(hfov)
    left_rgb_sensor.parameters["vfov"] = str(vfov)
    # The left RGB sensor will be 1.5 meters off the ground
    # and 0.25 meters to the left of the center of the agent
    left_rgb_sensor.position = 1.5 * habitat_sim.geo.UP + (cam_baseline / 2) * habitat_sim.geo.LEFT

    # Same deal with the right sensor
    right_rgb_sensor = habitat_sim.SensorSpec()
    right_rgb_sensor.uuid = "right_sensor"
    right_rgb_sensor.resolution = [height, width]
    right_rgb_sensor.parameters["hfov"] = str(hfov)
    right_rgb_sensor.parameters["vfov"] = str(vfov)
    # The right RGB sensor will be 1.5 meters off the ground
    # and 0.25 meters to the right of the center of the agent
    right_rgb_sensor.position = 1.5 * habitat_sim.geo.UP + (cam_baseline / 2) * habitat_sim.geo.RIGHT

    # Now let's do the exact same thing but for a depth camera stereo pair!
    left_depth_sensor = habitat_sim.SensorSpec()
    left_depth_sensor.uuid = "left_sensor_depth"
    left_depth_sensor.resolution = [height, width]
    left_depth_sensor.parameters["hfov"] = str(hfov)
    left_depth_sensor.parameters["vfov"] = str(vfov)
    left_depth_sensor.position = 1.5 * habitat_sim.geo.UP + (cam_baseline / 2) * habitat_sim.geo.LEFT
    # The only difference is that we set the sensor type to DEPTH
    left_depth_sensor.sensor_type = habitat_sim.SensorType.DEPTH

    right_depth_sensor = habitat_sim.SensorSpec()
    right_depth_sensor.uuid = "right_sensor_depth"
    right_depth_sensor.resolution = [height, width]
    right_depth_sensor.parameters["hfov"] = str(hfov)
    right_depth_sensor.parameters["vfov"] = str(vfov)
    right_depth_sensor.position = 1.5 * habitat_sim.geo.UP + (cam_baseline / 2) * habitat_sim.geo.RIGHT
    # The only difference is that we set the sensor type to DEPTH
    right_depth_sensor.sensor_type = habitat_sim.SensorType.DEPTH

    agent_config = habitat_sim.AgentConfiguration()  # set configuration for agent (id = 0)
    agent_config.sensor_specifications = [left_rgb_sensor, right_rgb_sensor, left_depth_sensor, right_depth_sensor]

    sim = habitat_sim.simulator.Simulator(habitat_sim.Configuration(backend_cfg, [agent_config]))

    # set agent position
    inital_state_agent = place_agent(sim, agent_config)
    # print("inital agent state: {0} ".format(inital_state_agent))
    print("inital agent's sensor state: {0} ".format(inital_state_agent.sensor_states))
    # set action
    _render(sim)